Forbidden means the peer was capable of doing what you wanted but wasn’t prepared to do it for you, e.g. you provided the wrong password, or weren’t allowed to call a particular number. You need to ask the person operating that peer why it rejected your request.
I had no trouble finding codec 95 issues on Google. I’d suggest: Res_rtp_asterisk.c: Unknown RTP codec 95 received from
Unfortunately, that thread dried up before enough information had been provided to work out what was going wrong.