We are starting our migration to MS Teams and have a POC group in Teams Only mode. A few of the Users, when trying to reply to a Skype chat, are intermittently getting this message where they should be typing their response: Due to an org policy change, you can enjoy a richer chat and calling experience. Continue your conversation here
When they attempt to reply, a new Teams Only chat opens. They are unable to reply to the original message in Interoperability. I have gone through all policies and I cannot find anything that has changed.
I'm going to assume those users using Skype are set to Islands mode. There is a known issue right now when they deployed native federation that broke interop when Islands mode is used from a Teams Only user to Islands users Skype initiated chat. The fix is supposed to be in by Monday last I read. It's in the service health dashboard.