Hi, I'm John! I will help you with this.
Are you having this issue when using the Teams app on Windows, or is it happening on the Teams website in Edge? If it’s the website, does it also sign you out every time you close the browser?
Any additional info about the issue you can provide will be helpful in diagnosing and resolving the issue.
Click "Add comment" to let me know.
Regards,
John J.D.