What it means
The call reached Asterisk and was matched to an endpoint, but the dialplan context of that endpoint has no extension for the dialled number.
Why it happens
- The provider sends the number in another format: with +, with 8, without the country code, or your SIP login instead of the DID.
- The endpoint points to a context that does not exist or is spelled differently.
- Pattern without an underscore (_X. vs X.).
How to fix it
- Look at the number in the message and add an extension for exactly that format, or a catch-all _X. / _+X. in that context.
- Check context= of the endpoint (pjsip show endpoint trunk) and dialplan show from-trunk.
- Test patterns in the dialplan tester before reloading.
Useful tools
Dialplan pattern tester · Number normalizer
Other Asterisk errors
- Request 'INVITE' from '<sip:…>' failed for '203.0.113.5:5060' - No matching endpoint found
- Request 'REGISTER' from '<sip:101@…>' failed for '198.51.100.7:5060' - Failed to authentic
- Contact 101/sip:101@192.168.1.50:5060;ob is now Unreachable. RTT: 0.000 msec
- No response received from 'sip:sip.provider.com' on registration attempt to 'sip:749512345
- Fatal response '403' received from 'sip:sip.provider.com' on registration attempt to 'sip:
- Retransmission timeout reached on transmission 1a2b3c@203.0.113.5 for seqno 102 (Critical