Ending Breakout rooms doesn't pull participants back to meeting

[RMD2021]

I have a user who is using breakout rooms during training sessions over Teams - they are the organiser and are successfully putting people into rooms.  But, when they close the breakout rooms, participants are not being brought back to the main meeting - they can see the notification that they are being brought back to the main room but nothing happens. All participants are having to leave the meeting and re-join.  Even the user as organiser had to leave and come back.

Any ideas why this isn't working?

[#2]

Hello @RMD2021  Are you selecting "close rooms," not "end meeting?"

Breakout rooms troubleshooting guide (microsoft.com)

[#3]

Yes they are selecting close rooms and the participants can see the announcement telling them they are being brought back to the main meeting but nothing happens from that point on.

[#4]

@RMD2021 Same thing happening to us for our meetings - also that delegates can't then access the original call to get back in.  Been happening since last Monday, before, never had this issue.

[#5]

I have been training using the same set of parameters each time for 95 sessions. The last two sessions has had this same issue. All participants go into the breakout room, but when I choose "Close" to end the breakout session, they are not pulled back into the main session. They have to leave the meeting and rejoin. The ability to communicate with them through chat or any other means is also disabled, so many do not know what to do and are lost. Please advise. @RMD2021