Q2698 Suddenly can't connect to 3G networks (GSM only)

Hi All,
We have a Q2698 running in a system, where it happily was connected to the Telstra 3G network for a number of days. Suddenly, it dropped offline and upon further inspection, the only service provider it can see (via AT+COPS=?) is a Vodafone 2G GSM service. A second identical system returns the 2G plus 3 other 3G services via the AT+COPS=? command and is still working fine.

Antenna has been checked and is ok. The fault is definitely within the modem module as the fault transfers over to the other system when swapped.

Is it likely to be a fault or a configuration issue? Can someone suggest a fix please?

Thanks for your time,
Terry

Hello,
This problem needs a detailed technical analysis. Please contact your Technical support in Sierra Wireless or Sierra Wireless distributor to provide you the solution.

Thanks & Regards,
Moderator

you can check below AT commands to see the modem status:
AT!GSTATUS?
AT+WOPEN?
AT!MAPUART?