Conversations involving multiple participants, allowing collaboration and information sharing in Teams
>Just to let you know that I had the same problem and I needed to logout Teams, Quit, Restart the App and Login again so that the channel history was corrected and all issues corrected.
Worked for me in similar situation. A channel was displaying the error message.
Quit (from Teams context menu on task bar) + start Teams app didn't help.
Sign out (which closed the Teams app, too) and starting Teams again did help.