BG77 sms error 303

Technical Subjects
1

I am trying to send a sms with a BG77. first the sending of an sms worked but now i always get +cms error:303. I am sending this to the module:

AT+CMGF=1OK
AT+CMGS=“+31xxxxxxx” batrijspanning te laag op dit moment 1 volt
+CMS ERROR: 303

could someone tell me how I can solve this issue?

2

Hi,
If possible SMS service is in arrears？
As we can see, 303 means operation not support.
Could you please help check with operator?
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