This was due to an attempt by someone to rob the casino (as I mentioned in my previous post).

Money was 'won' (albeit the withdrawal was blocked due to security measures) which resulted in the bank temporarily running a negative balance. The computer (as programmed) immediately went to work on building the balance again which resulted in this scenario. This attempted robbery was detected within an hour and the casino was taken offline while the problem was fixed. Logs were checked, and players who unfairly 'lost' had their accounts manually reimbursed. The casino then moved on...so should you..