Every time I start the app, it asks me to log in. Once I do, within a few seconds it logs me out again and tells me I need to log-in again. (See attached screenshot.)
If you sign into an additional device while logged into another device of the same type, you will be logged out automatically on the first device. This might happen if you signed into Zoom on a home computer and then sign in from an office computer; the home computer might still be signed in and cause this error.