Hi ,
I'm Nik, an independent advisor here to assist you with this issue.
To narrow down the issue, please check if you see a similar experience on MS Teams web app.
Go to access 'Teams Web App' https//teams.microsoft.com, use "Use the web app instead" option to open teams in a browser and check the outcome. It will help to isolate the issue with the desktop app.
If the issue is specific to the MS Teams desktop app, then try clearing app cache by these steps and try again:
https://www.uvm.edu/it/kb/article/clearing-team...
If you still see the issue, please disconnect any external devices(e.g. Display monitor; camera, headset etc.) and try again.
Please let me know the outcome, and I'll further look into this.
Disclaimer:
Note: Link shared in this conversation is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it.
Regards
Nik