Re: Bugged arena
If it's what I think it is, it has happened to some players as well. You can ask for your missing rewards by contacting the Help Center, you can find the link below. They can be slow at responding to your ticket (can take days especially these days), but usually they're helpful with missing item cases.
You can also prepare a screenshot of your bugged Arena page, as well as taking note of your Player ID. You can find your player ID by tapping the setting icon in the game, then go to the build version. The Help Center may need the player ID to identify your profile, so that they can give you your missing rewards/fix the bug in your profile.
