The apple Tv app with all my purchased movies and tv episodes disappeared from my apple Tv today.
I didn’t think that would be possible, unless you re-configured your Apple ID to a country or country-like region that doesn’t have Apple Media Services.
Could it be that Apple TV app has been moved accidentally to an unexpected place on the Home Screen? Could it be inside an app folder? Customize the Apple TV Home Screen - Apple Support
I have restarted the apple Tv
That is a good start for troubleshooting. If the suggestions above didn’t apply or didn’t resolve it, then please contact the Apple Support staff for further assistance.