Dear Wilson Jong,
Thanks for your inquiry in Quectel forum.
Could you help to check it can restore if you restart the module to have a try ? If it is hard to restart the module, how about to send AT command to check the module status ? You can send AT+CPIN? to check the SIM card is OK via USB AT port. And you also can check the SIM card connection is normal or not. Please help to provide more information, then we can help you to fix the issue. Thanks!
Dear Wilson Jong,
Error code 13 means that SIM failure, which means that there may have the interference on SIM card circuit. So it is better to confirm it. You also can try to send AT+CFUN=0, then send AT+CFUN=1 to check whether it can restore. If still have the error information, please check the SIM card circuit design. Thanks!
Dear Wilson Jong,
If the method i provide to you still not working, it is better to check whether the SIM card connection is OK, you can unplug then plug the SIM card. If still have the issue, it is better to check the SIM card circuit of your board. Thanks!