Unfortunately, it is not possible to remove an access key from one account and apply it to another. In this situation, you will have to buy a new, unused access key.
To be honest none of us can be much help for you here. You'll have a much better respond if you contact the gw support. Explain your situation to them and have all of the detail handy.
If you're lucky they'll deactive you key and sent you a new one.
Contact support, tell them what is your problem. Most important don't give up after a few automated responses keep sending tickets until a real persons sends you a response.