Skins and heads missing

So, last night I got my offline account to Xbox Live Gold. I was looking forward to playing Borderlands 2 online, but I noticed a major issue with all of my characters. Every non-quest, non-challenge head and skin I had is gone. Some of these things were stupid rare to get, like Bunker’s head for the Siren and the pure black skin from the four Hyperion assassins for the Commando. What happened? I am upset to see all the grinding, farming, and effort I put in gone. How do I undo this? All I want is what I earned. Please help.

That’s one I haven’t heard of before. All I can suggest is that you file a support ticket here to see if they have any clues:

The bad news is that support can’t restore (or give you codes for) items lost form your inventory.