I've seen that before. I believe the guy was paid way wrong on a parlay or straight bet (like +40000 instead of +400) and then went on a huge run with a bigger balance. When they found out the first bet was graded wrong, they cancelled all the bets after it and awarded him the correct amount for the orginal bet. Problem is that he laready withdrew a lot of it, and after the changes were made he was in the negative. That might not be the exact details because its been years ago, just the best I can remember
He's a dick if you have issues..as you can see