[Henry17]

If you have done nothing wrong then you have nothing to worry about. Unfortunately there are so many people pulling scams on sites. Something brought you to security's attention. It could have been a transfer to or from someone who committed fraud, a friend who logged on from your machine once and then did something, someone you beat might have had charge-backs etc. As long as you know you didn't do anything then you'll be fine. It could take some time though. I'd expect to be locked out for at least 3 weeks, Which sucks but don't blame the sites blame the losers who try to defraud sites.

They can't give you any explanation. It is very frustrating but until they are sure you were not involved and are just collateral damage giving out information will just educate people who scam sites.