MC 7455 - CMS Error 300 when sending SMS

Hello, I’m using Raspbian and the modem is connected with the MC AirPrime development kit.

at+cops: 0,0,“Verizon Wireless”,7
at+cgreg: 0,1
at+csq: 22,99

After trying to send SMS,

at+cmgf=1
OK
at+cmgs=""

The prompt skips a lot of lines and returns
+CMS ERROR: 300

I’ve verified that the SIM works by sending & receiving SMS on an Android. What could be causing the error?

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

Thanks & Regards,
Moderator