Merged calls dropping

Brass Contributor

I am testing the merge call feature and have a scenario where the original called member of the merged call gets dropped.


  • Party A (PSTN) calls party B (Teams)
  • Party B answers and then performs a consultative transfer to party C (Teams)
  • Party A performs the call merge and A, B and C are connected.
  • After about 1 minute party A is dropped from the call and party B & C remain connected.


The same test done where the call is merged with another PSTN number instead of a Teams user works fine.


On my initial test there was a BYE message from Teams > SBC > PSTN saying "Removing modality controller as the conversation has ended " and with all subsequent tests the BYE is sent from the PSTN > SBC > Teams.


I tested with two different SBCs (AudioCodes & Oracle) connected to the same Teams tenant and both have the same behavior.


3 Replies

Can you check one thing on the licensing front if the we have the Microsoft Teams Audio Conferencing license assigned to the account?

Additionally in which location/country are trying to test the services?

With Regards,
Satish U
The Teams accounts have E5 with audio conferencing enabled, the tenant and accounts are in the USA region.

When the call drops, Teams displays a pop up message saying "We ran into a problem, try again in a few minutes"
I was able reproduce this in two other customer tenants so it seems like this an issue on the service side. I've opened case with Microsoft to assist.