SIM Registraion Issue

I don’t know, seems it is showing 5G band
you can compare with the specification of MC7455

I checked this, the bands supported by Modem are available in my area.

And they are 800 MHz (3), 1800 MHz (7) and 2600 MHz (20)

And I tried to set SETRAT to LTE only but after restarting the ModemManager it comes back to same state

what is the return of AT!GSTATUS? now?

with the same SIM card in mobile phone with APN internet4, the LTE connection is OK, right?

AT!GSTATUS?

Current Time: 577604 Temperature: 41
Reset Counter: 3 Mode: ONLINE
System mode: WCDMA PS state: Not attached
WCDMA band: WCDMA 2100
WCDMA channel: 10575
GMM (PS) state:DEREGISTERED PLMN SEARCH
MM (CS) state: IDLE PLMN SEARCH

WCDMA L1 state:L1M_ACQ LAC: 139E (5022)
RRC state: DISCONNECTED UTRAN Cell ID: FFFFFFFF (4294967295)
RxM RSSI C0: — RxD RSSI C0: —
RxM RSSI C1: — RxD RSSI C1: —

OK

And yes, with APN set to ‘internet4’, it works in mobile.

didn’t you limit to LTE only?

Yes, I did limit, but it’s changing back to the earlier again

why it’s changing back to the earlier again?

I’m not sure, let me see

Checked but, didn’t find any clue regarding this one.

But, when I set to LTE, it tries to register. But after some messages, it goes to UMTS & LTE mode…

<<<<<< QMUX:
<<<<<< length = 46
<<<<<< flags = 0x80
<<<<<< service = “nas”
<<<<<< client = 5
<<<<<< QMI:
<<<<<< flags = “indication”
<<<<<< transaction = 21004
<<<<<< tlv_length = 34
<<<<<< message = “Serving System” (0x0024)
<<<<<< TLV:
<<<<<< type = “Serving System” (0x01)
<<<<<< length = 6
<<<<<< value = 02:02:02:02:01:08
<<<<<< translated = [ registration_state = ‘not-registered-searching’ cs_attach_state = ‘detached’ ps_attach_state = ‘detached’ selected_network = ‘3gpp’ radio_interfaces = '{ [0] = 'lte ‘}’ ]
<<<<<< TLV:
<<<<<< type = “Data Service Capability” (0x11)
<<<<<< length = 1
<<<<<< value = 00
<<<<<< translated = {}
<<<<<< TLV:
<<<<<< type = “Current PLMN” (0x12)
<<<<<< length = 10
<<<<<< value = F4:00:05:00:05:65:6C:69:73:61
<<<<<< translated = [ mcc = ‘244’ mnc = ‘5’ description = ‘elisa’ ]
<<<<<< TLV:
<<<<<< type = “MNC PCS Digit Include Status” (0x29)
<<<<<< length = 5
<<<<<< value = F4:00:05:00:00
<<<<<< translated = [ mcc = ‘244’ mnc = ‘5’ includes_pcs_digit = ‘no’ ]

And then later on, it goes to

ModemManager[1765]: [/dev/cdc-wdm0] received generic indication (translated)…
<<<<<< QMUX:
<<<<<< length = 33
<<<<<< flags = 0x80
<<<<<< service = “nas”
<<<<<< client = 4
<<<<<< QMI:
<<<<<< flags = “indication”
<<<<<< transaction = 21024
<<<<<< tlv_length = 21
<<<<<< message = “Serving System” (0x0024)
<<<<<< TLV:
<<<<<< type = “Serving System” (0x01)
<<<<<< length = 6
<<<<<< value = 02:02:02:00:01:00
<<<<<< translated = [ registration_state = ‘not-registered-searching’ cs_attach_state = ‘detached’ ps_attach_state = ‘detached’ selected_network = ‘unknown’ radio_interfaces = '{ [0] = 'none ‘}’ ]
<<<<<< TLV:
<<<<<< type = “Data Service Capability” (0x11)
<<<<<< length = 1
<<<<<< value = 00
<<<<<< translated = {}
<<<<<< TLV:
<<<<<< type = “Detailed Service Status” (0x22)
<<<<<< length = 5
<<<<<< value = 00:03:00:00:00
<<<<<< translated = [ status = ‘none’ capability = ‘cs-ps’ hdr_status = ‘none’ hdr_hybrid = ‘no’ forbidden = ‘no’ ]

Didn’t you use at!selrat to limit to LTE only?

Yes, I set that.

After, it comes back to UMTS & LTE only

Do you mean AT!SELRAT? will change automatically?
this does not quite make sense

Yes, after checking in few seconds or minutes, it changes automatically.

no idea, i never met such issue that the setting is changed automatically
It is hard to debug if your platform is not stable and not under control and changing the setting as it wants

What needs to be done in this case ?

no idea, i never met such issue that the setting is changed automatically

Maybe you can install a Virtual machine of Windows image and see if it will also change the setting automatically