DID number which Mapped to VoIP (SIP) is not Working

If you mapped the DID to VoIP line which is using the SIP protocol please check that the DID number includes the prefix.

For example:

If the DID is 8745441221 and the prefix is 44 (UK) the mapping should be

SIP/64.16.210.54/448745441221 and NOT SIP/64.16.210.54/8745441221.