Feb 26 2019 08:58 AM
Feb 26 2019 09:11 AM
Feb 26 2019 10:46 AM
That's easy to reproduce if you have registered Teams as the chat app for Office, and I'm almost certain it's a bug (actually more than one bug, as in my case it opens a "just me" chat with another person...).
Sep 24 2020 07:46 PM
I've encountered this when "Saving a message". The just me chat is like a group conversation where you are the first member. You rename the group and add members.
However, can't do this by manually creating a group chat and specifying only your email address.