AT+COPS=? returns ERROR: 3

IoT Modules LPWA Module
1

I’m using a BG96 module from RAK Wireless, and a Hologram SIM.
When I issue the command AT+COPS=?, I get an “ERROR: 3” in response.

Any ideas?

2

the cmd will show available network ， e.g

AT+cops=?
2019-10-01_10:14:41:046]+COPS: (2,“Sprint”,“Sprint”,“311490”,7),(1,“AT&T”,“AT&T”,“310410”,7),(1,“AT&T”,“AT&T”,“310410”,2),(3,“Verizon”,“Verizon”,“311480”,7),(3,“T-Mobile”,“T-Mobile”,“310260”,7),(3,“T-Mobile”,“T-Mobile”,“310260”,2),(3,“313 100”,“313 100”,“313100”,7),(0-4),(0-2

if the response is err 3 ， that means there is not available network , pls check your SIM card provision,
thanks