It is possible to 'dispute' a payment with your CC company. Generally, this relates to payments which you have not authorised. In this case, it sounds like you did authorise the original payment, so you may be on dodgy ground here. However, a lot depends the individual at the CC company you speak to - When some dodgy online charges appears on my Amex account, the first person I spoke to was telling me that I'd have to pay these charges while they investigated them. I told her very clearly that I wasn't paying the charges, I'd close the account if they tried to make me pay, and I'd see them in court if necessary. I was then passed through to someone in their fraud section who agreed to credit the charges straight away.