Correct HOLD/Call transfer indication in VoLTE

Hello colleagues.

I faced a problem related more to a PCRF, but I think that an SBC is a root of problem. In VoLTE scenarios when User A calls User B and then calls User C, SBC sends AAR with the same Framed-IP-address for call legs between User A and SBC in both calls "User A -> User B" and "User A -> User C". This causes the problem on PCRF , it associates two different Rx sessions with the same Gx session. So when the second call between user A and user C is terminated, PCRF removes the "common"