stopped receiving text messages

[treebeard]

I'm not sure how to install the AT command. Does anyone know which package it belongs to?

After reading the other thread, I was able to run
mmcli -m 0 --messaging-list-sms 

But that returned "No sms messages were found".

If the modem is clogged, mmcli doesn't seem to know about it.

AT commands are text strings sent to the modem.  mmcli has a way to do this but it doesn't work on newer versions unless ModemManager is in debug mode so that adds some complexity.  Other documented techniques involve using atinout or minicom.  I've used picocom successfully.

That thread I referenced has the appropriate AT commands but writing up the sort of instructions that should be in the wiki is a bit beyond me right now.