If you want to delete a group that you have previously added to Favorites, you have to:
1. Go to the "You" tab.
2. Tap on "Favorites".
3. Tap on the three dots near the group you want to delete.
4. Tap on "Delete".
5. Confirm by tapping "Delete" again. 
Note: You can only delete the groups that you have previously added.
The Favorites feature is available only through Paid Subscription and only on Android devices.
You can also watch our video tutorial on how to delete a favorite group here.
How do I subscribe?
How do I create a favorite group? (Android only)
How do I share a favorite group? (Android only)