I would say best is (if you made a trade request with him) give him a negative rating. You are able to go to the police if your account gets stolen though. Perhaps also make a complaint to epvp regarding your situation as this states about ID Verified Users:
Edit: Perhaps make his name public in your post aswell. If he is active on the Seafight section people should be aware that there are scammers around, and know their names.
