You need to contact the seller again or if you used PayPal, open a case. In many cases you can ask for Refund and provide PayPal or the payment processor all the details regarding the payment. At this point the seller will be forced to answer or its account will be blocked. You will receive your code or the money back to your account, even if he decides to move the money to another account. Use the email in the payment info to request a status update and then proceed to other options.