I think my cloud saved data must have got corrupted or something. Was playing fine. Took an error and when I restarted the game all my characters were gone (years worth as you can imagine)! I tried deleting local saves to resynch from the cloud. Still gone. Tried logging in from a different Xbox... characters still gone. Contacted Microsoft who said... you need to contact Blizzard. I posted a msg on their boards, but thought someone from here might know how to fix. Thanks.
While I've never had this exact issue, I have had similar problems on console before. For me, I usually just take a break for several hours and when I return the issues have been resolved. I'm not saying that this will be the solution, but it might help just to wait and try again!