I recently sold a website over on Flippa and received the payment for it via PayPal. I've been getting everything together here, ready to send over all the files, etc. BUT I just checked my PayPal account and saw that this guy filed a dispute and now my account is in the negative. I contacted the buyer and he said he got nervous because he didn't hear back from me for one day. I told him I would not proceed until he canceled the dispute. He told me that he is unable to and that I have to send everything over to him first. Is he right? How should I handle this?