Apple TV App signing in issue on Fire TV Cube

I am getting an error when trying to login to the Apple TV application on my Fire TV Cube. See screenshot below... 

I am using a 2nd generation Fire tv cube which is compatible with the Apple TV app. When I first downloaded the Apple TV app it worked fine for the first few months on the Fire tv cube. Now, for the past several weeks I get this error. 

I have already uninstalled and reinstalled the app. I have cleared the cache/data/force stop, which neither worked. I have checked for app updates and updates to the firetv cube, followed by a reboot and recheck for any updates. Everything is current and up to date. 

I have seen several other threads on the Fire stick and an OS update seemed to work, but not with my fire tv cube. 

Any help would be appreciated.