SAMSUNG / APPLE TV APP ISSUE RESOLVED !!
I've had an issue with AppleTV on my Samsung TV for over a year and I couldn't get it resolved. Many Reddit threads and Apple threads and a lot of reading led me to nothing ... I just wanted my AppleTV to work again. I spoke to Larry at AppleTv Tech and he fixed... so damn simple. My goodness I laughed.
Steps as per Larry the Tech :
1. Uninstall AppleTV app
2. Unplug TV
3. Wait 2 minutes
4. Plug back in
5. Reinstall AppleTV
6. Enjoy again.