Conversations involving multiple participants, allowing collaboration and information sharing in Teams
Hello frskippy,
Good day!
I'm Jericho, a fellow customer and an individual advisor. I am happy to assist you!
Apparently, this is a known and a bug experience in Teams for users who already left the Team and for external users as well.
To solve this try to uninstall the app, and delete the Teams related temporary files in there C:\Users\Your.User\AppData and then try to reinstall the app again and see if that solves issue.
Hope that helps! Please let me know if you have other queries/concerns.