I have an issue with outbound calls using Teams Direct Routing on Oracle SBCs. We are seeing SIP calls dropping at around 10 minutes with Teams responding with the following SIP 403 Forbidden message:
REASON: Q.850;cause=63;text="2d3ce374-1fc2-4c17-adf6-2e997f090562;Target Client has not supplied Outgoing Negotiation Request link."
I have seen another post with this issue, however, the cause is not the same and doesn't really provide the required fix. The carrier is sending two re-INVITEs within a couple of second of each other, however the second contains no SDP (but Content-Length is set to 0 which is a valid SIP message as per rfc3261) and Teams response with the above 403 Forbidden message, thus disconnecting the outbound call.
Would anyone have an idea of where we could look or fix this on the Direct Routing SBC? We do have a case with Microsoft open, however they are suggesting it's the re-INVITE with no SDP at fault.