Velobet Account Closed - Winnings Confiscated Without Justification

I signed up for Velobet and put in £3500, choosing not to get a bonus. I asked to withdraw money after my balance reached £6200. Velobet then told me I could only take out £1000 because they had supposedly added £200 to my account, which I never asked for or agreed to. They took the rest of the money without a good reason. I made a complaint and was told that the issue had been raised. Four days later, after asking for an update, I was told that my account had been closed without warning. I played fair and turned down all bonuses, but Velobet took my real winnings and closed my account without giving me a good reason.