The seller has been suspended. Never end to a new seller who wants gift cards or any form of unsecure payment. We have a middleman service for these type of services. I'm not sure despite all the warnings on the site people continue to do it. The only recommendation I can give people is to contact Apple and recover your gift card. Someone did it and they just removed it from the other guys account and put it on his account. That's all you can do.
Here is a complete Middleman Service Guide Middleman Service Guide | PlayerUp - MMO Accounts Marketplace. Most Secure Player 2 Player Network.