Also, you might want to check out this discussion from just a few days ago with a fellow comrade about a similar MS Teams problem:

https://lists.kamailio.org/pipermail/sr-users/2020-April/108868.html  

On Tue, Apr 14, 2020 at 4:23 PM Sergiu Pojoga <pojogas@gmail.com> wrote:
Well... most likely you didn't fix it, at least not properly. There's no such requirement to have a single RR in the 200 OK, especially only the one from the sender's original invite.
By this logic, Kamailio can't insert it's own RR to keep itself in the call's path. I can assure you that's not the case in reality.

On Tue, Apr 14, 2020 at 3:12 PM Nasida Yuriy <nasida@live.ru> wrote:
Yes, sure, need to fix Record-Route. The question was how exactly :)
Well.  I just fixed it by the way. 200 OK had to have only one record-route (which MS sent in initial invite). Otherwise MS ignore it without any response.




От: sr-users <sr-users-bounces@lists.kamailio.org> от имени Ovidiu Sas <osas@voipembedded.com>
Отправлено: 14 апреля 2020 г. 20:32
Кому: Kamailio (SER) - Users Mailing List <sr-users@lists.kamailio.org>
Тема: Re: [SR-Users] kamailio integration with MS teams.
 
The instructions are pretty clear in the sense that you need to fix
the Record-Route header.
You don't need to touch the Contact header for in-dialog requests/replies.

Regards,
Ovidiu Sas


On Tue, Apr 14, 2020 at 12:19 PM Nasida Yuriy <nasida@live.ru> wrote:
>
> Hi guys,
>
>
> Do you have some expirience with kamailio integration with MS teams ?
>
>
> I follow the instructon from here
> https://skalatan.de/en/blog/kamailio-sbc-teams
>
> TLS part is configured correctly. I also got OPTIONS pings working between MS teams and kamailio by following of  this instruction. That is very good.
>
>  But... There is issues with outbound calls from MS teams to kamailo.
>
>
> MS side send INVITE, kamailio responds with 180 and 200 OK, but looks like MS ignores us. I know that I probably should use record_route_preset function here to modify Record-Route headers to satisfy MS wishes.
>
> But nothing helps. I also tried to modify contact header in 200 OK like it was done for OPTIONS - no luck.
>
> Anyone has a working example of kamailio files for MS team ?
> Or at least sucessful pcap with them.
>
> I can be wrong but looks like MS doesn't respect RFC at all.
>
>
> Thanks.
>
>
>
>
> Regards,
> Team lead
>
> _______________________________________________
> Kamailio (SER) - Users Mailing List
> sr-users@lists.kamailio.org
> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users



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http://www.voipembedded.com

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