IOT device is not registering to Network

IOT device is built with Quectel BG95-M3 modem and Supports LTE-CAT M, GSM. I am trying to register the device to LTE CAT M simulator network. But device is not registering to Network at all. The below message is shown always.

2000/01/01 00:11:42:build/cellmodule.c:405-Modem still searching
2000/01/01 00:11:52:cellmodemd/cellmodemd_main.c:259-Timed out on response to command: AT+CEREG?.

With AT command enter manually.

Enter Command: at+cops=?
Executing Command: at+cops=?\r\n
2021/12/18 01:55:09:cellmodemd/cellmodemd_main.c:259-Timed out on response to command: at+cops=?
Can’t get proper response
Hit enter for next command or q to quit.
W-2021/12/18 01:55:43:build/cellmodule.c:1810-Got CME string: CME ERROR: 3
2021/12/18 01:55:43:cellmodemd/cellmodemd_main.c:118-CME Error:3

Can you suggest me how to register a device with AT commands support. I would need sequence of AT commands to register Network.

You can follow this AT command set for preliminary investigation.
Quectel_BG95&BG77&BG600L_Series_AT_Commands_Manual_V2.0.pdf (1.4 MB)