MC7455: EMM attach failed

I have a Sierra Wireless AirPrime MC7455 connected to a Linux box with Centos 7.

# uname -a
Linux phone.wfprod.com 4.20.7-1.el7.elrepo.x86_64 #1 SMP Wed Feb 6 13:17:46 EST 2019 x86_64 x86_64 x86_64 GNU/Linux

The MC7455 is in this USB adapter, with a Sprint SIM card (part number SIMGLW416Q).

I went on Tello’s website and gave them the IMEI and SIM numbers and got a phone number.
The plan has unlimited talk/text and no data.

I have mostly been using this tutorial, but the firmware flash is from github/danielewood/sierra-wireless-modems
Also, I am using the Sprint firmware instead of the Generic.

The error I am getting is:

at+cgatt=1
+CME ERROR: no network service
at+ceer
+CEER: EMM attach failed

Sometimes I got this error instead of EMM attach failed (I’ve tried the whole process a few times):

+CEER: User Aauthentication faile

I am going to try adding data to the plan and see what that does for me.


Full command output:

# minicom -D /dev/ttyUSB2

ati
Manufacturer: Sierra Wireless, Incorporated
Model: MC7455
Revision: SWI9X30C_02.30.01.01 r7792 CARMD-EV-FRMWR2 2018/07/13 02:24:52
MEID: 35907206321180
IMEI: 359072063211805
IMEI SV: 16
FSN: LQ842740430210
+GCAP: +CGSM


OK
at!entercnd="A710"
OK
at!rmareset=1
!RMARESET: DEVICE REBOOT REQUIRED

Items Restored:  2150
Items Deleted:   0

ERROR
at!reset
OK

// unplug and re-plug

# minicom -D /dev/ttyUSB2

at!entercnd="A710"
OK
at!usbcomp=1,1,10D
OK
at!reset
OK

// unplug and re-plug

// using libqmi-1.22.0 installed from source (CentOS doesn't include qmi-firmware-update)
# deviceid=`lsusb | grep -i -E '1199:9071|1199:9079|413C:81B6' | awk '{print $6}'`
# qmi-firmware-update --update -d "$deviceid" SWI9X30C_02.30.01.01.cwe SWI9X30C_02.30.01.01_SPRINT_002.045_000.nvu
loading device information before the update...
setting firmware preference:
  firmware version: '02.30.01.01'
  config version:   '002.045_000'
  carrier:          'SPRINT'
rebooting in download mode...
download mode detected
downloading cwe image: SWI9X30C_02.30.01.01.cwe (64.5 MB)...
finalizing download... (may take more than one minute, be patient)
successfully downloaded in 52.82s (1.2 MB/s)
downloading cwe image: SWI9X30C_02.30.01.01_SPRINT_002.045_000.nvu (16.5 kB)...
finalizing download... (may take more than one minute, be patient)
successfully downloaded in 0.06s (287.8 kB/s)
rebooting in normal mode...
normal mode detected

------------------------------------------------------------------------
    NOTE: in order to validate which is the firmware running in the
    module, the program will wait for a complete boot; this process
    may take some time and several retries.
------------------------------------------------------------------------

waiting some time for the device to boot...
loading device information after the update (1/12)...
waiting some time for the device to boot...
loading device information after the update (2/12)...

------------------------------------------------------------------------

   original firmware revision was:
      SWI9X30C_02.24.05.06 r7040 CARMD-EV-FRMWR2 2017/05/19 06:23:09
   original running firmware details:
      Model: MC7455
      Boot version: SWI9X30C_02.24.05.06
      AMSS version: SWI9X30C_02.24.05.06
      SKU ID: 1103578
      Carrier ID: 1
      Config version: 002.026_000
   original firmware preference details:
      image 'modem': unique id '002.026_000', build id '02.24.05.06_GENERIC'
      image 'pri': unique id '002.026_000', build id '02.24.05.06_GENERIC'

   new firmware revision is:
      SWI9X30C_02.30.01.01 r7792 CARMD-EV-FRMWR2 2018/07/13 02:24:52
   new running firmware details:
      Model: MC7455
      Boot version: SWI9X30C_02.30.01.01
      AMSS version: SWI9X30C_02.30.01.01
      SKU ID: 1103578
      Carrier ID: 11
      Config version: 002.045_000
   new firmware preference details:
      image 'modem': unique id '002.045_000', build id '02.30.01.01_SPRINT'
      image 'pri': unique id '002.045_000', build id '02.30.01.01_SPRINT'

   NOTE: this device supports stored image management
   with qmicli operations:
      --dms-list-stored-images
      --dms-select-stored-image
      --dms-delete-stored-image

   NOTE: this device supports firmware preference management
   with qmicli operations:
      --dms-get-firmware-preference
      --dms-set-firmware-preference

------------------------------------------------------------------------

firmware update operation finished successfully

// unplug and re-plug

# minicom -D /dev/ttyUSB2
ati
Manufacturer: Sierra Wireless, Incorporated
Model: MC7455
Revision: SWI9X30C_02.30.01.01 r7792 CARMD-EV-FRMWR2 2018/07/13 02:24:52
MEID: 35907206321180
IMEI: 359072063211805
IMEI SV: 16
FSN: LQ842740430210
+GCAP: +CGSM


OK
at!entercnd="A710"
OK
at!usbcomp=1,1,1009
OK
at!usbcomp?
Config Index: 1
Config Type:  1 (Generic)
Interface bitmask: 00001009 (diag,modem,mbim)

OK
at!impref="SPRINT"
OK
at!reset
OK

# minicom -D /dev/ttyUSB1

at!entercnd="A710"
OK
at!impref?
!IMPREF:
 preferred fw version:    02.30.01.01
 preferred carrier name:  SPRINT
 preferred config name:   SPRINT_002.045_000
 current fw version:      02.30.01.01
 current carrier name:    SPRINT
 current config name:     SPRINT_002.045_000

OK
// changed from 1 to 3 because of sprint firmware (1 is the ota update APN)
// got APN from bestmvno.com
at+cgdcont=3,"IPV4V6","n.mi.ispsn"
OK
at+cgdcont?
+CGDCONT: 1,"IP","otasn","0.0.0.0",0,0,0,0
+CGDCONT: 3,"IPV4V6","n.mi.ispsn","0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0",0,0,0,0

OK
at!custom="IPV6ENABLE",0
OK
at!selrat=06
OK
at!gstatus?
!GSTATUS:
Current Time:  68               Temperature: 26
Reset Counter: 2                Mode:        ONLINE
System mode:   LTE              PS state:    Not attached
LTE band:      No band          LTE bw:      Unknown
LTE Rx chan:   0                LTE Tx chan: 4294967295
LTE CA state:  ACTIVE                   LTE Scell band:B31
LTE Scell bw:3 MHz              LTE Scell chan:0
EMM state:     Deregistered     Attach Needed
RRC state:     RRC Releasing
IMS reg state: No Srv

PCC RxM RSSI:  0                RSRP (dBm):  0
PCC RxD RSSI:  0                RSRP (dBm):  0
SCC RxM RSSI:  0                RSRP (dBm):  0
SCC RxD RSSI:  0                RSRP (dBm):  0
Tx Power:      --               TAC:         45FC (17916)
RSRQ (dB):     127.9            Cell ID:     00000000 (0)
SINR (dB):


OK

at!band=0A,"B25",0,0000000001000000
OK
at!band=0B,"B26",0,0000000002000000
OK
at!band=0C,"B41",0,0000010000000000
OK
at!band=0D,"Sprint (All)",0,0000010003000000
OK
at!band=0C
OK

at!gstatus?
!GSTATUS:
Current Time:  235              Temperature: 27
Reset Counter: 2                Mode:        ONLINE
System mode:   LTE              PS state:    Not attached
LTE band:      B41              LTE bw:      20 MHz
LTE Rx chan:   41094            LTE Tx chan: 4294967295
LTE CA state:  NOT ASSIGNED
EMM state:     Deregistered     Attach Needed
RRC state:     RRC Idle
IMS reg state: No Srv

PCC RxM RSSI:  -78              RSRP (dBm):  -110
PCC RxD RSSI:  -95              RSRP (dBm):  -138
Tx Power:      --               TAC:         1F0F (7951)
RSRQ (dB):     -11.7            Cell ID:     03FAA401 (66757633)
SINR (dB):      8.8


OK
at+cgatt=1
+CME ERROR: no network service
at+ceer
+CEER: EMM attach failed

OK
at!gstatus?
!GSTATUS:
Current Time:  269              Temperature: 27
Reset Counter: 2                Mode:        ONLINE
System mode:   LTE              PS state:    Not attached
LTE band:      B41              LTE bw:      20 MHz
LTE Rx chan:   41094            LTE Tx chan: 4294967295
LTE CA state:  NOT ASSIGNED
EMM state:     Deregistered     Attach Needed
RRC state:     RRC Idle
IMS reg state: No Srv

PCC RxM RSSI:  -78              RSRP (dBm):  -109
PCC RxD RSSI:  -95              RSRP (dBm):  -137
Tx Power:      --               TAC:         1F0F (7951)
RSRQ (dB):     -11.4            Cell ID:     03FAA401 (66757633)
SINR (dB):      9.6


OK

Ok, I added 1GB of data to the Tello plan and I get this consistently:

at+cgatt=1
+CME ERROR: no network service
at+ceer
+CEER: Requested service option not subscribed

I am going to try connecting to AT&T with my cell phone’s sim card.

I flashed the AT&T firmware and attempted to connect, and now at+cgatt=1 returns OK but ata returns NO CARRIER.

With selrat=06:

at+cgatt=1
OK
ata
NO CARRIER
at+ceer
+CEER: EMM detached

With selrat=00:

at+cgatt=1
OK
ata
NO CARRIER
at+ceer
+CEER: No cause information available

‘“emm detached” mc7455’ returns no results on Google.

Note: I used the AT&T SIM from my OnePlus One (the same sim was previously used in an iPhone SE) and the representative at AT&T said it could be put in any other phone when I switched from the iPhone.


Full output:
# minicom -D /dev/ttyUSB1
at!entercnd="A710"
OK
at!usbcomp=1,1,10D
OK
at!reset
OK

# deviceid=`lsusb | grep -i -E '1199:9071|1199:9079|413C:81B6' | awk '{print $6}'`
# qmi-firmware-update --update -d "$deviceid" SWI9X30C_02.30.01.01.cwe SWI9X30C_02.30.01.01_ATT_002.049_003.nvu
loading device information before the update...
setting firmware preference:
  firmware version: '02.30.01.01'
  config version:   '002.049_003'
  carrier:          'ATT'
rebooting in download mode...
download mode detected
downloading cwe image: SWI9X30C_02.30.01.01.cwe (64.5 MB)...
finalizing download... (may take more than one minute, be patient)
successfully downloaded in 52.82s (1.2 MB/s)
downloading cwe image: SWI9X30C_02.30.01.01_ATT_002.049_003.nvu (36.5 kB)...
finalizing download... (may take more than one minute, be patient)
successfully downloaded in 0.06s (591.7 kB/s)
rebooting in normal mode...
normal mode detected

------------------------------------------------------------------------
    NOTE: in order to validate which is the firmware running in the
    module, the program will wait for a complete boot; this process
    may take some time and several retries.
------------------------------------------------------------------------

waiting some time for the device to boot...
loading device information after the update (1/12)...
waiting some time for the device to boot...
loading device information after the update (2/12)...
waiting some time for the device to boot...
loading device information after the update (3/12)...
waiting some time for the device to boot...
loading device information after the update (4/12)...

------------------------------------------------------------------------

   original firmware revision was:
      SWI9X30C_02.30.01.01 r7792 CARMD-EV-FRMWR2 2018/07/13 02:24:52
   original running firmware details:
      Model: MC7455
      Boot version: SWI9X30C_02.30.01.01
      AMSS version: SWI9X30C_02.30.01.01
      SKU ID: 1103578
      Carrier ID: 11
      Config version: 002.045_000
   original firmware preference details:
      image 'modem': unique id '002.045_000', build id '02.30.01.01_SPRINT'
      image 'pri': unique id '002.045_000', build id '02.30.01.01_SPRINT'

   new firmware revision is:
      SWI9X30C_02.30.01.01 r7792 CARMD-EV-FRMWR2 2018/07/13 02:24:52
   new running firmware details:
      Model: MC7455
      Boot version: SWI9X30C_02.30.01.01
      AMSS version: SWI9X30C_02.30.01.01
      SKU ID: 1103578
      Carrier ID: 4
      Config version: 002.049_003
   new firmware preference details:
      image 'modem': unique id '002.049_003', build id '02.30.01.01_ATT'
      image 'pri': unique id '002.049_003', build id '02.30.01.01_ATT'

   NOTE: this device supports stored image management
   with qmicli operations:
      --dms-list-stored-images
      --dms-select-stored-image
      --dms-delete-stored-image

   NOTE: this device supports firmware preference management
   with qmicli operations:
      --dms-get-firmware-preference
      --dms-set-firmware-preference

------------------------------------------------------------------------

firmware update operation finished successfully

# minicom -D /dev/ttyUSB2

at!entercnd="A710"
OK
at!usbcomp=1,1,1009
OK
at!usbcomp?
Config Index: 1
Config Type:  1 (Generic)
Interface bitmask: 00001009 (diag,modem,mbim)

OK
at!impref="ATT"
OK
at!impref?
!IMPREF:
 preferred fw version:    02.30.01.01
 preferred carrier name:  ATT
 preferred config name:   ATT_002.049_003
 current fw version:      02.30.01.01
 current carrier name:    ATT
 current config name:     ATT_002.049_003

OK
at!reset
OK

# minicom -D /dev/ttyUSB1

at!gstatus?
!GSTATUS:
Current Time:  122              Temperature: 25
Reset Counter: 7                Mode:        ONLINE
System mode:   LTE              PS state:    Attached
LTE band:      B5               LTE bw:      10 MHz
LTE Rx chan:   2450             LTE Tx chan: 20450
LTE CA state:  NOT ASSIGNED
EMM state:     Registered       Normal Service
RRC state:     RRC Idle
IMS reg state: No Srv

PCC RxM RSSI:  -68              RSRP (dBm):  -105
PCC RxD RSSI:  -98              RSRP (dBm):  -140
Tx Power:      --               TAC:         6A49 (27209)
RSRQ (dB):     -19.4            Cell ID:     07F67B01 (133593857)
SINR (dB):      2.4


OK
at+cgatt=1
OK
at!gstatus?
!GSTATUS:
Current Time:  366              Temperature: 25
Reset Counter: 7                Mode:        ONLINE
System mode:   WCDMA            PS state:    Attached
WCDMA band:    WCDMA 850
WCDMA channel: 4457
MM (CS) state: IDLE             NORMAL SERVICE

WCDMA L1 state:L1M_PCH_SLEEP    LAC:           CDEC (52716)
RRC state:   DISCONNECTED       UTRAN Cell ID: 0698484F (110643279)
RxM RSSI C0:   -90              RxD RSSI C0:  ---
RxM RSSI C1:    ---             RxD RSSI C1:  ---


OK
at+cgdcont?
+CGDCONT: 1,"IPV4V6","broadband","0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0",0,0,0,0

OK
at!selrat=06
OK
at!gstatus?
!GSTATUS:
Current Time:  497              Temperature: 25
Reset Counter: 7                Mode:        ONLINE
System mode:   LTE              PS state:    Attached
LTE band:      B5               LTE bw:      10 MHz
LTE Rx chan:   2450             LTE Tx chan: 20450
LTE CA state:  INACTIVE                 LTE Scell band:B2
LTE Scell bw:10 MHz             LTE Scell chan:1000
EMM state:     Registered       Normal Service
RRC state:     RRC Connected
IMS reg state: No Srv

PCC RxM RSSI:  -68              RSRP (dBm):  -105
PCC RxD RSSI:  -98              RSRP (dBm):  -140
SCC RxM RSSI:  -89              RSRP (dBm):  -112
SCC RxD RSSI:  -104             RSRP (dBm):  -134
Tx Power:      --               TAC:         6A49 (27209)
RSRQ (dB):     -20.0            Cell ID:     07F67B01 (133593857)
SINR (dB):     -3.0


OK
at+cgatt=1
OK
ata
NO CARRIER
at+ceer
+CEER: EMM detached

OK
at!gstatus?
!GSTATUS:
Current Time:  542              Temperature: 25
Reset Counter: 7                Mode:        ONLINE
System mode:   LTE              PS state:    Attached
LTE band:      B5               LTE bw:      10 MHz
LTE Rx chan:   2450             LTE Tx chan: 20450
LTE CA state:  NOT ASSIGNED
EMM state:     Registered       Normal Service
RRC state:     RRC Idle
IMS reg state: No Srv

PCC RxM RSSI:  -68              RSRP (dBm):  -105
PCC RxD RSSI:  -98              RSRP (dBm):  -140
Tx Power:      --               TAC:         6A49 (27209)
RSRQ (dB):     -20.0            Cell ID:     07F67B01 (133593857)
SINR (dB):     -3.8


OK
at+cgact=1,1
OK
ata
NO CARRIER
at+ceer
+CEER: EMM detached

OK
at!gstatus
ERROR
at!gstatus?
!GSTATUS:
Current Time:  602              Temperature: 24
Reset Counter: 7                Mode:        ONLINE
System mode:   LTE              PS state:    Attached
LTE band:      B5               LTE bw:      10 MHz
LTE Rx chan:   2450             LTE Tx chan: 20450
LTE CA state:  NOT ASSIGNED
EMM state:     Registered       Normal Service
RRC state:     RRC Idle
IMS reg state: No Srv

PCC RxM RSSI:  -68              RSRP (dBm):  -104
PCC RxD RSSI:  -97              RSRP (dBm):  -139
Tx Power:      --               TAC:         6A49 (27209)
RSRQ (dB):     -18.3            Cell ID:     07F67B01 (133593857)
SINR (dB):     -3.4


OK
at!gstatus?
!GSTATUS:
Current Time:  150              Temperature: 24
Reset Counter: 1                Mode:        ONLINE
System mode:   LTE              PS state:    Attached
LTE band:      B5               LTE bw:      10 MHz
LTE Rx chan:   2450             LTE Tx chan: 20450
LTE CA state:  NOT ASSIGNED
EMM state:     Registered       Normal Service
RRC state:     RRC Idle
IMS reg state: No Srv

PCC RxM RSSI:  -69              RSRP (dBm):  -105
PCC RxD RSSI:  -98              RSRP (dBm):  -140
Tx Power:      --               TAC:         6A49 (27209)
RSRQ (dB):     -18.7            Cell ID:     07F67B01 (133593857)
SINR (dB):      1.2


OK
at!selrat=?
!SELRAT: Index, Name
00, Automatic
01, UMTS 3G Only
02, Not Supported
03, Not Supported
04, Not Supported
05, Not Supported
06, LTE Only
07, Not Supported
08, Not Supported
09, Not Supported
0A, Not Supported
0B, Not Supported
0C, Not Supported
0D, Not Supported
0E, Not Supported
0F, Not Supported
10, Not Supported
11, UMTS and LTE Only
12, Not Supported
13, Not Supported
14, Not Supported


OK
at!selrat=00
OK
at+cgatt=1
OK
ata
NO CARRIER
at+ceer
+CEER: No cause information available

OK
at!gstatus
ERROR
at!gstatus?
!GSTATUS:
Current Time:  663              Temperature: 24
Reset Counter: 1                Mode:        ONLINE
System mode:   LTE              PS state:    Attached
LTE band:      B5               LTE bw:      10 MHz
LTE Rx chan:   2450             LTE Tx chan: 20450
LTE CA state:  NOT ASSIGNED
EMM state:     Registered       Normal Service
RRC state:     RRC Idle
IMS reg state: No Srv

PCC RxM RSSI:  -67              RSRP (dBm):  -105
PCC RxD RSSI:  -98              RSRP (dBm):  -140
Tx Power:      --               TAC:         6A49 (27209)
RSRQ (dB):     -19.6            Cell ID:     07F67B01 (133593857)
SINR (dB):      0.8


OK

Update: I flashed the generic firmware and Used r.mi.ispsn as the APN and I’m getting this now:

at+cgdcont?
+CGDCONT: 1,"IPV4V6","r.mi.ispsn","0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0",0,0,0,0

OK
at+cgatt=1
OK
at!gstatus?
!GSTATUS:
Current Time:  246              Temperature: 25
Reset Counter: 1                Mode:        ONLINE
System mode:   LTE              PS state:    Attached
LTE band:      B41              LTE bw:      20 MHz
LTE Rx chan:   41292            LTE Tx chan: 41094
LTE CA state:  NOT ASSIGNED
EMM state:     Registered       Normal Service
RRC state:     RRC Idle
IMS reg state: No Srv

PCC RxM RSSI:  -84              RSRP (dBm):  -119
PCC RxD RSSI:  -89              RSRP (dBm):  -126
Tx Power:      --               TAC:         1F0F (7951)
RSRQ (dB):     -15.1            Cell ID:     03F6DB3B (66509627)
SINR (dB):      1.8

OK
at+csq?
+CME ERROR: operation not allowed
at+ceer
+CEER: EMM detached

So I’m making progress, but I still can’t dial a call. I get NO CARRIER:

atdxxxxxxxxxx;
NO CARRIER
at+ceer
+CEER: Regular deactivation

OK

Let’s stick with AT&T because it is easier to troubleshoot.
Your AT&T configuration (and APN) was correct because the modem attached to AT&T.
On Linux switch to RMNET mode instead of MBIM. (at!usbcomp)
It is recommended to use the Sierra drivers (GobiNet, GobiSerial available on https://source.sierrawireless.com)

Make sure that the modem is attached and acquired an IP address.
At!gstatus?
At+cgcontrdp
Then to initiate the datacall:
At!scact=1
(should return with OK)

After this on Linux NTWK manager should bringup dhcp between the modem & PC.
Modem manager will also try to access the modem.
Of you can call dhclient yourself on embedded systems.

Ok, I re-flashed the ATT firmware and gave that a try.

I got another no network service error on at!scact.

at!entercnd="A710"
OK
at!impref="ATT"
OK
at!impref?
!IMPREF:
 preferred fw version:    02.30.01.01
 preferred carrier name:  ATT
 preferred config name:   ATT_002.049_003
 current fw version:      02.30.01.01
 current carrier name:    ATT
 current config name:     ATT_002.049_003

OK
at!gstatus?
!GSTATUS:
Current Time:  177              Temperature: 23
Reset Counter: 3                Mode:        ONLINE
System mode:   LTE              PS state:    Attached
LTE band:      B5               LTE bw:      10 MHz
LTE Rx chan:   2450             LTE Tx chan: 19000
LTE CA state:  NOT ASSIGNED
EMM state:     Registered       Normal Service
RRC state:     RRC Idle
IMS reg state: No Srv

PCC RxM RSSI:  -70              RSRP (dBm):  -105
PCC RxD RSSI:  -74              RSRP (dBm):  -114
Tx Power:      --               TAC:         6A49 (27209)
RSRQ (dB):     -17.4            Cell ID:     07F67B01 (133593857)
SINR (dB):     -2.6


OK
at+cgatt=1
OK
At+cgcontrdp
+CGCONTRDP: 1,5,broadband,10.251.184.48,,172.26.38.1,

OK
At!scact=1
+CME ERROR: no network service
at+ceer
+CEER: No cause information available

OK

you need to install GobiNet and change it to RMNET.

Ok, I installed GobiNet and GobiSerial from https://source.sierrawireless.com/resources/airprime/software/usb-drivers-linux-qmi-software-s2,-d-,36n2,-d-,55/

And i set at!usbcomp=1,1,10D.

I also installed ModemManager and setup the device whitelist in /lib/udev/rules.d/78-mm-whitelist-internal-modem.rules as follows:

ACTION!="add|change|move", GOTO="mm_whitelist_internal_modem_end"
    ATTRS{idVendor}=="1199", ATTRS{idProduct}=="9071", ENV{ID_MM_DEVICE_PROCESS}="1"
    LABEL="mm_whitelist_internal_modem_end"

However, ModemManager isn’t recognizing the modem firmware:

Feb 19 19:16:01 phone ModemManager[14170]: <warn>  Couldn't get detailed info for PRI image with build ID '02.30.01.01_ATT': QMI protocol error (71): 'InvalidQmiCommand'
Feb 19 19:16:02 phone ModemManager[14170]: <warn>  Couldn't get detailed info for PRI image with build ID '02.30.01.01_GENERIC': QMI protocol error (71): 'InvalidQmiCommand'
Feb 19 19:16:02 phone ModemManager[14170]: <warn>  Couldn't get detailed info for PRI image with build ID '02.30.01.01_SPRINT': QMI protocol error (71): 'InvalidQmiCommand'
Feb 19 19:16:02 phone ModemManager[14170]: <warn>  No valid firmware images listed. Assuming firmware unsupported.
Feb 19 19:16:02 phone ModemManager[14170]: <info>  Modem: state changed (unknown -> disabled)

So I manually enabled the modem with mmcli -m 0 -e:

Feb 19 19:16:04 phone ModemManager[14170]: <info>  Modem /org/freedesktop/ModemManager1/Modem/0: state changed (disabled -> enabling)
Feb 19 19:16:04 phone ModemManager[14170]: <warn>  (ttyUSB2): port attributes not fully set
Feb 19 19:16:04 phone ModemManager[14170]: <info>  Modem /org/freedesktop/ModemManager1/Modem/0: 3GPP Registration state changed (unknown -> registering)
Feb 19 19:16:04 phone ModemManager[14170]: <info>  Modem /org/freedesktop/ModemManager1/Modem/0: 3GPP Registration state changed (registering -> home)
Feb 19 19:16:05 phone ModemManager[14170]: <info>  Modem /org/freedesktop/ModemManager1/Modem/0: state changed (enabling -> registered)
successfully enabled the modem

But ifconfig is still not showing the interface, even after restarting NetworkManager.

How do I get the wwan interface to show in ifconfig?

Can you check modem enumeration?
By default the kernel loads the default drivers qmi_wwan and qcserial , you have to blacklist these.
vi /etc/modprobe.d/blacklist-modem.conf
blacklist qmi_wwan
blacklist qcserial

reboot.

try to bringup the session without modem manager.
just disable it and issue at!scact=1 and call dhclient

Awesome! I can now attach to the AT&T and Sprint networks and use LTE data!

At first I thought Sprint was not going to work, but I tried it with the Generic firmware and it worked.

Thank you!