I was playing Arkham Origins earlier and just completed the Shadow Vigilante challenges for the achievement. For some reason the achievement didn't pop so I went to the guide to double check. I was apparently still signed in, but it was showing my gamerscore as 0 with NO games played. I restarted my Xbox and signed back in. On the dash my account shows my actual gamerscore which is 22973, and all my achievements are there when I go to the guide as long as I'm on the dashboard.
I tried going back into the game, it loads up and I press the Guide button, and my account goes back to showing 0G. I thought the problem may have just been with Arkham Origins, since the game has been causing my Xbox to freeze quite a bit, so I tried another game and the same thing happened. I don't know what to do!