I faced some problems (the infinite loop) when trying to download app from App Store on my iPhone XS (iOS 14.6). I guess there's a bug to continue the process on mobile.

So I decided to try it on my Macbook and it's fixed!

My solution is to open TV app on mac then follow the process below: 
1. Open TV app on Mac
2. Click Sign In menu
3. You'll get same error like on mobile. Click Review. 
3. Fill your apple ID
4. Continue the process until finish. 

[![enter image description here][1]][1] 

[![enter image description here][2]][2]


  [1]: https://i.sstatic.net/eSQ4s.jpg
  [2]: https://i.sstatic.net/10i3C.jpg