stopped receiving text messages

[treebeard]

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.

The simplest probable solution:
1) enter "sudo su -", and then your password when prompted, to get a root shell.  The shell prompt should now read "root@mobian" or "root@pine" or something similar depending on your hostname.
2) enter/paste the text between the square brackets:  [echo -ne "AT+CMGD=,2\r" > /dev/ttyUSB2] .  I don't think you'll see a response.
3) enter "exit" to exit the root shell and return to your normal shell.
4) test reception of an SMS message.

The AT command tells the modem to purge all stored messages marked as revceived.  This will not show you the messages stored, nor the maximum capacity, nor provide any other diagnostic info, but should at least clear the problem.

Please report your results.