If your friend is getting disconnected multiple times a night you should try the troubleshooting in the help article below.
What do I do if I am disconnected on Xbox One with the error message "Unable to Connect to Server. Please Check Your Internet Connection"?
Deleting the local save data may also help in resolving this issue.
To delete save data on the Xbox One:
- Go to Games.
- Highlight The Elder Scrolls Online: Tamriel Unlimited tile and press the [Menu] button of the controller.
- Select Manage Game.
- Highlight and select Save Data for the desired user.
- Select Delete.
- You'll be prompted to confirm deletion of this game save data:
- Choose "Delete Everywhere" This will remove your saved data from this console, the cloud, and all other consoles you play on
If none of these help, you can contact customer support for additional assistance.
I uninstalled and reinstalled the game tonight after 10 game freezes and 2 disconnects. Just froze again after only 30mins in cyrodiil. FIX. YOUR. GAME.