Members disappeared from private Teams channel

Question

Hi, we use Teams for Education at our college. One of our teachers had an issue with the private channels he has been creating in one of his Teams. He added the students to each channel, and they even managed to post there. However, when he went back to the Team some time later those private channels showed no members at all. The members had disappeared. Has this happened before? Can you help?

Answer 1

Just to exclude any possible caching-related issues (those happen a lot), have him try with a private browser session. Also check the in-client channel update log, by pressing the little "i" icon in the top right corner, then selecting Updates at the bottom. You as an admin can also run a search against the Unified audit log for any related events: https://learn.microsoft.com/en-us/microsoft-365/compliance/search-the-audit-log-in-security-and-compliance?view=o365-worldwide