HL7588 not connecting i.e. acquiring bearer channel after attach

If I understood well, once the modem is attached the connection i.e. acquiring the bearer channel is straight-forward. With HL7588 it seems that this is not working (most of times).

I have used AT commands and MBIM to make a stable procedure for RAW-IP connection. However it seems the modem fails to acquire the bearer channel (time out is 15 seconds) most of the times:

max command size : 512
openning device for the session.
sending open message.
sending              : 16 bytes
  header_type        : 0x0001
  header_length      : 0x0010
  header_transaction : 0x0001
  00000000  01 00 00 00 10 00 00 00 01 00 00 00 00 02 00 00  ................

reading              : 16 bytes
  header_type        : 0x80000001  MBIM_MESSAGE_TYPE_OPEN_DONE
  status_code        : 0x0000 - success
  header_length      : 0x0010
  header_transaction : 0x0001
  00000000  01 00 00 80 10 00 00 00 01 00 00 00 00 00 00 00  ................

sending              : 48 bytes
  header_type        : 0x0003
  header_length      : 0x0030
  header_transaction : 0x0002
  00000000  03 00 00 00 30 00 00 00 02 00 00 00 01 00 00 00  ....0...........
  00000010  00 00 00 00 A2 89 CC 33 BC BB 8B 4F B6 B0 13 3E  .......3...O...>
  00000020  C2 AA E6 DF 01 00 00 00 00 00 00 00 00 00 00 00  ................

reading              : 264 bytes
  header_type        : 0x80000003  MBIM_MESSAGE_TYPE_COMMAND_DONE
  command_id         : 0x0001
  status_code        : 0x0000 - success
  header_length      : 0x0108
  header_transaction : 0x0002
  00000000  03 00 00 80 08 01 00 00 02 00 00 00 01 00 00 00  ................
  00000010  00 00 00 00 A2 89 CC 33 BC BB 8B 4F B6 B0 13 3E  .......3...O...>
  00000020  C2 AA E6 DF 01 00 00 00 00 00 00 00 D8 00 00 00  ................
  00000030  01 00 00 00 01 00 00 00 01 00 00 00 02 00 00 00  ................
  00000040  3F 00 00 00 03 00 00 00 01 00 00 00 08 00 00 00  ?...............
  00000050  00 00 00 00 00 00 00 00 40 00 00 00 1E 00 00 00  ........@.......
  00000060  60 00 00 00 3C 00 00 00 9C 00 00 00 3C 00 00 00  `...<.......<...
  00000070  30 00 31 00 34 00 37 00 36 00 39 00 30 00 30 00  0.1.4.7.6.9.0.0.
  00000080  30 00 31 00 34 00 33 00 30 00 37 00 37 00 00 00  0.1.4.3.0.7.7...
  00000090  4D 00 32 00 4D 00 5F 00 37 00 31 00 36 00 30 00  M.2.M._.7.1.6.0.
  000000A0  5F 00 41 00 54 00 54 00 5F 00 4D 00 42 00 49 00  _.A.T.T._.M.B.I.
  000000B0  4D 00 5F 00 44 00 45 00 42 00 55 00 47 00 5F 00  M._.D.E.B.U.G._.
  000000C0  57 00 57 00 5F 00 30 00 31 00 2E 00 58 00 4D 00  W.W._.0.1...X.M.
  000000D0  4D 00 37 00 31 00 36 00 30 00 5F 00 56 00 31 00  M.7.1.6.0._.V.1.
  000000E0  2E 00 31 00 5F 00 4D 00 42 00 49 00 4D 00 5F 00  ..1._.M.B.I.M._.
  000000F0  4E 00 41 00 4E 00 44 00 5F 00 41 00 44 00 41 00  N.A.N.D._.A.D.A.
  00000100  50 00 54 00 5F 00 52 00                          P.T._.R.

  devicetype        : 0x0001 - embedded
  cellularclass     : 0x0001
  voiceclass        : 0x0001 - no-voice
  simclass          : 0x0002
  dataclass         : 0x003F
  smscaps           : 0x0003
  controlcaps       : 0x0001
  maxsessions       : 0x0008
  deviceid          : 014769000143077
  firmwareinfo      : M2M_7160_ATT_MBIM_DEBUG_WW_01.
  hardwareinfo      : XMM7160_V1.1_MBIM_NAND_ADAPT_R
mbim_end has been called.
>>>>>>>>>>>>>> pinstate
max command size : 512
sending              : 48 bytes
  header_type        : 0x0003
  header_length      : 0x0030
  header_transaction : 0x0003
  00000000  03 00 00 00 30 00 00 00 03 00 00 00 01 00 00 00  ....0...........
  00000010  00 00 00 00 A2 89 CC 33 BC BB 8B 4F B6 B0 13 3E  .......3...O...>
  00000020  C2 AA E6 DF 04 00 00 00 00 00 00 00 00 00 00 00  ................

reading              : 60 bytes
  header_type        : 0x80000003  MBIM_MESSAGE_TYPE_COMMAND_DONE
  command_id         : 0x0004
  status_code        : 0x0000 - success
  header_length      : 0x003C
  header_transaction : 0x0003
  00000000  03 00 00 80 3C 00 00 00 03 00 00 00 01 00 00 00  ....<...........
  00000010  00 00 00 00 A2 89 CC 33 BC BB 8B 4F B6 B0 13 3E  .......3...O...>
  00000020  C2 AA E6 DF 04 00 00 00 00 00 00 00 0C 00 00 00  ................
  00000030  03 00 00 00 01 00 00 00 05 00 00 00              ............

required pin        : 3 - pin2
remaining attempts  : 5
mbim_end has been called.
>>>>>>>>>>>>>> attached ?
max command size : 512
sending              : 48 bytes
  header_type        : 0x0003
  header_length      : 0x0030
  header_transaction : 0x0004
  00000000  03 00 00 00 30 00 00 00 04 00 00 00 01 00 00 00  ....0...........
  00000010  00 00 00 00 A2 89 CC 33 BC BB 8B 4F B6 B0 13 3E  .......3...O...>
  00000020  C2 AA E6 DF 0A 00 00 00 00 00 00 00 00 00 00 00  ................

reading              : 76 bytes
  header_type        : 0x80000003  MBIM_MESSAGE_TYPE_COMMAND_DONE
  command_id         : 0x000A
  status_code        : 0x0000 - success
  header_length      : 0x004C
  header_transaction : 0x0004
  00000000  03 00 00 80 4C 00 00 00 04 00 00 00 01 00 00 00  ....L...........
  00000010  00 00 00 00 A2 89 CC 33 BC BB 8B 4F B6 B0 13 3E  .......3...O...>
  00000020  C2 AA E6 DF 0A 00 00 00 00 00 00 00 1C 00 00 00  ................
  00000030  00 00 00 00 02 00 00 00 20 00 00 00 80 F0 FA 02  ........ .......
  00000040  00 00 00 00 00 E1 F5 05 00 00 00 00              ............

  nwerror             : 0x0000 - unknown
  packetservicestate  : 0x0002 - attached
  uplinkspeed         : 50000000
  downlinkspeed       : 100000000
mbim_end has been called.
>>>>>>>>>>>>>> already attached
>>>>>>>>>>>>>> connect to network
Thu Oct 10 19:33:38 UTC 2019
max command size : 512
connect
  protocol           : ipv4v6
  access point name  : ltemobile.apn
sending              : 136 bytes
  header_type        : 0x0003
  header_length      : 0x0088
  header_transaction : 0x0005
  00000000  03 00 00 00 88 00 00 00 05 00 00 00 01 00 00 00  ................
  00000010  00 00 00 00 A2 89 CC 33 BC BB 8B 4F B6 B0 13 3E  .......3...O...>
  00000020  C2 AA E6 DF 0C 00 00 00 01 00 00 00 58 00 00 00  ............X...
  00000030  00 00 00 00 01 00 00 00 3C 00 00 00 1A 00 00 00  ........<.......
  00000040  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000050  00 00 00 00 00 00 00 00 03 00 00 00 7E 5E 2A 7E  ............~^*~
  00000060  4E 6F 72 72 73 6B 65 6E 7E 5E 2A 7E 6C 00 74 00  Norrsken~^*~l.t.
  00000070  65 00 6D 00 6F 00 62 00 69 00 6C 00 65 00 2E 00  e.m.o.b.i.l.e...
  00000080  61 00 70 00 6E 00 00 00                          a.p.n...

mbim message timeout
mbim_end has been called.
Thu Oct 10 19:33:54 UTC 2019
max command size : 512
connect
  protocol           : ipv4v6
  access point name  : ltemobile.apn
sending              : 136 bytes
  header_type        : 0x0003
  header_length      : 0x0088
  header_transaction : 0x0006
  00000000  03 00 00 00 88 00 00 00 06 00 00 00 01 00 00 00  ................
  00000010  00 00 00 00 A2 89 CC 33 BC BB 8B 4F B6 B0 13 3E  .......3...O...>
  00000020  C2 AA E6 DF 0C 00 00 00 01 00 00 00 58 00 00 00  ............X...
  00000030  00 00 00 00 01 00 00 00 3C 00 00 00 1A 00 00 00  ........<.......
  00000040  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000050  00 00 00 00 00 00 00 00 03 00 00 00 7E 5E 2A 7E  ............~^*~
  00000060  4E 6F 72 72 73 6B 65 6E 7E 5E 2A 7E 6C 00 74 00  Norrsken~^*~l.t.
  00000070  65 00 6D 00 6F 00 62 00 69 00 6C 00 65 00 2E 00  e.m.o.b.i.l.e...
  00000080  61 00 70 00 6E 00 00 00                          a.p.n...

mbim message timeout
mbim_end has been called.
Thu Oct 10 19:34:10 UTC 2019
max command size : 512
connect
  protocol           : ipv4v6
  access point name  : ltemobile.apn
sending              : 136 bytes
  header_type        : 0x0003
  header_length      : 0x0088
  header_transaction : 0x0007
  00000000  03 00 00 00 88 00 00 00 07 00 00 00 01 00 00 00  ................
  00000010  00 00 00 00 A2 89 CC 33 BC BB 8B 4F B6 B0 13 3E  .......3...O...>
  00000020  C2 AA E6 DF 0C 00 00 00 01 00 00 00 58 00 00 00  ............X...
  00000030  00 00 00 00 01 00 00 00 3C 00 00 00 1A 00 00 00  ........<.......
  00000040  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  00000050  00 00 00 00 00 00 00 00 03 00 00 00 7E 5E 2A 7E  ............~^*~
  00000060  4E 6F 72 72 73 6B 65 6E 7E 5E 2A 7E 6C 00 74 00  Norrsken~^*~l.t.
  00000070  65 00 6D 00 6F 00 62 00 69 00 6C 00 65 00 2E 00  e.m.o.b.i.l.e...
  00000080  61 00 70 00 6E 00 00 00                          a.p.n...