Extension not found in context 'public'

I’m running asterisk alongside openbts and SIP for a personal GSM network. I’m running on Ubuntu 14.04. When I place the call the error below is what normally appears without debug logging. The pastebin link leads to the log file that is produced with verbose set to 5.

chan_sip.c:25450 handle_request_invite: Call from ‘’ (127.0.0.1:5062) to extension ‘2222222222’ rejected because extension not found in context ‘public’.

pastebin.com/tReUqGbH

Can´t see your pastebin, but the error is basic and pretty clear. Your extension doesn’t exist in the context Public.

So check you context called public and create the extension.

The configuration is missing from the pastebin, but I would say the problem is that there is no sip.conf entry for IMSI310260608893334 and allowguest is enabled.

My guess is this is an OpenBTS user. I hope they have a radio telephony licence.