troubleshooting Chatty / modem? no SMS outbound

[bcnaz]

Any pointers on troubleshooting a modem that keeps unregistering?

I switched to USMobile SIM and cannot send SMS / MMS.  SMS & MMS _inbound_ does work (Yes, MMS in Chatty! ) and calls _do_ work inbound & outbound (voice is loud & clear!). 

Just SMS / MMS outbound is NOT working.  And when I try outbound, the modem goes back to "Unregistered", searching, and re-registers; but the "sent" SMS is never received ... logs make it sound like the modem is being rejected.

When I put this USMobile SIM into my daily driver (a MotoG8 running stock Android), everything works.  So it's not a borked SIM. 

One odd thing: my Moto8G modem detects this SIM's cellular network as "T-Mobile", but the APN & MMSC details in Android do indeed match USMobile's website for Androids.  Those APN & MMSC details are what I have setup in Mobian Bookworm.

I've put ModemManager into debug mode but don't really know what to look for ... and perhaps debug is overkill.  Did I miss something obvious in setting up USMobile?

Logs that repeat are below that have rejects in them:

---

Code:

Feb 13 10:07:12 mobian ModemManager[604]: <info>  [modem0] power state updated: on
Feb 13 10:07:12 mobian eg25manager[505]: Response: [+QIND: SMS DONE]
Feb 13 10:07:12 mobian eg25manager[505]: Executed soft sleep sequence
Feb 13 10:07:13 mobian ModemManager[604]: <info>  [modem0] 3GPP registration state changed (unknown -> searching)
Feb 13 10:07:13 mobian ModemManager[604]: <warn>  [modem0] couldn't load operator code: Current operator MCC/MNC is still unknown
Feb 13 10:07:13 mobian ModemManager[604]: <warn>  [modem0] couldn't load operator name: Current operator id is still unknown
Feb 13 10:07:13 mobian ModemManager[604]: <info>  [modem0] state changed (enabling -> searching)
Feb 13 10:07:13 mobian mmsdtng[2272]: ../plugins/modemmanager.c:modem_state_changed_cb() State Change: Old State: 5 New State: 7, Reason: 1
Feb 13 10:07:13 mobian mmsdtng[2272]: ../plugins/modemmanager.c:mmsd_mm_get_modem_state() MM_MODEM_GOOD_STATE: 7
Feb 13 10:07:13 mobian mmsdtng[2272]: ../plugins/modemmanager.c:mmsd_mm_state() MMSD_MM_STATE_READY
Feb 13 10:07:13 mobian mmsdtng[2272]: ../plugins/modemmanager.c:mmsd_mm_state() Setting Bearer Handler
Feb 13 10:07:13 mobian mmsdtng[2272]: ../src/service.c:mms_service_set_bearer_handler() service 0x55928f13d0 handler 0x5568a66820
Feb 13 10:07:13 mobian NetworkManager[500]: <info>  [1644768433.5067] modem["cdc-wdm0"]: modem state changed, 'enabling' --> 'searching' (reason: user-requested)
Feb 13 10:07:52 mobian ModemManager[604]: <info>  [modem0] 3GPP registration state changed (searching -> idle)
Feb 13 10:07:52 mobian ModemManager[604]: <info>  [modem0] state changed (searching -> enabled)
Feb 13 10:07:52 mobian NetworkManager[500]: <info>  [1644768472.1250] modem["cdc-wdm0"]: modem state changed, 'searching' --> 'enabled' (reason: unknown)
Feb 13 10:07:52 mobian mmsdtng[2272]: ../plugins/modemmanager.c:modem_state_changed_cb() State Change: Old State: 7 New State: 6, Reason: 0
Feb 13 10:07:52 mobian mmsdtng[2272]: ../plugins/modemmanager.c:mmsd_mm_get_modem_state() MM_MODEM_GOOD_STATE: 6
Feb 13 10:07:52 mobian ModemManager[604]: <warn>  [modem0] network reject indication received
Feb 13 10:07:52 mobian mmsdtng[2272]: ../plugins/modemmanager.c:mmsd_mm_state() MMSD_MM_STATE_READY
Feb 13 10:07:52 mobian ModemManager[604]: <warn>  [modem0]   service domain: ps
Feb 13 10:07:52 mobian mmsdtng[2272]: ../plugins/modemmanager.c:mmsd_mm_state() Setting Bearer Handler
Feb 13 10:07:52 mobian ModemManager[604]: <warn>  [modem0]   radio interface: lte
Feb 13 10:07:52 mobian mmsdtng[2272]: ../src/service.c:mms_service_set_bearer_handler() service 0x55928f13d0 handler 0x5568a66820
Feb 13 10:07:52 mobian ModemManager[604]: <warn>  [modem0]   reject cause: ps-services-in-location-area-not-allowed
Feb 13 10:07:52 mobian ModemManager[604]: <warn>  [modem0] network reject indication received
Feb 13 10:07:52 mobian ModemManager[604]: <warn>  [modem0]   service domain: ps
Feb 13 10:07:52 mobian ModemManager[604]: <warn>  [modem0]   radio interface: lte
Feb 13 10:07:52 mobian ModemManager[604]: <warn>  [modem0]   reject cause: ps-services-in-location-area-not-allowed
Feb 13 10:07:53 mobian ModemManager[604]: <warn>  [modem0] network reject indication received
Feb 13 10:07:53 mobian ModemManager[604]: <warn>  [modem0]   service domain: cs-ps
Feb 13 10:07:53 mobian ModemManager[604]: <warn>  [modem0]   radio interface: lte
Feb 13 10:07:53 mobian ModemManager[604]: <warn>  [modem0]   reject cause: plmn-not-allowed
Feb 13 10:07:53 mobian ModemManager[604]: <warn>  [modem0] network reject indication received
Feb 13 10:07:53 mobian ModemManager[604]: <warn>  [modem0]   service domain: cs-ps
Feb 13 10:07:53 mobian ModemManager[604]: <warn>  [modem0]   radio interface: lte
Feb 13 10:07:53 mobian ModemManager[604]: <warn>  [modem0]   reject cause: roaming-in-location-area-not-allowed
Feb 13 10:07:54 mobian ModemManager[604]: <info>  [modem0] 3GPP registration state changed (idle -> registering)
Feb 13 10:07:54 mobian ModemManager[604]: <info>  [modem0] 3GPP registration state changed (registering -> home)
Feb 13 10:07:54 mobian ModemManager[604]: <info>  [modem0] state changed (enabled -> registered)
Feb 13 10:07:55 mobian mmsdtng[2272]: ../plugins/modemmanager.c:modem_state_changed_cb() State Change: Old State: 6 New State: 8, Reason: 0
Feb 13 10:07:55 mobian mmsdtng[2272]: ../plugins/modemmanager.c:mmsd_mm_get_modem_state() MM_MODEM_GOOD_STATE: 8
Feb 13 10:07:55 mobian mmsdtng[2272]: ../plugins/modemmanager.c:mmsd_mm_state() MMSD_MM_STATE_READY
Feb 13 10:07:55 mobian mmsdtng[2272]: ../plugins/modemmanager.c:mmsd_mm_state() Setting Bearer Handler
Feb 13 10:07:55 mobian mmsdtng[2272]: ../src/service.c:mms_service_set_bearer_handler() service 0x55928f13d0 handler 0x5568a66820
Feb 13 10:08:47 mobian NetworkManager[500]: <info>  [1644768527.4008] modem["cdc-wdm0"]: modem state changed, 'enabled' --> 'searching' (reason: unknown)
Feb 13 10:08:49 mobian ModemManager[604]: <warn>  [modem0] network reject indication received
Feb 13 10:08:49 mobian ModemManager[604]: <warn>  [modem0]   service domain: cs-ps
Feb 13 10:08:49 mobian ModemManager[604]: <warn>  [modem0]   radio interface: lte
Feb 13 10:08:49 mobian ModemManager[604]: <warn>  [modem0]   reject cause: plmn-not-allowed

Not certain it will apply here & now,
But an issue that sounded like your description -- from the Brave Heart days,
Is "Regions & Languages" completely filled in,  in the settings ?