First you can do is to double check if you entered correct BTC address and see if you had minimum one confirmation for your transaction.
Use any bitcoin explorer to confirm.
You also need to pay exact amount of btc.
Pay to the Bitcoin address xxxxxxxxxxxxxxxxxxxxxxxxxxx. Once your transaction has 1 confirmation, revisit this page and then use the form which will appear in order to wear your new membership. Your transaction will not be accepted until it has 1 confirmation. Bitcoin network fees and exchange/wallet withdrawal fees will not count toward your payment.
We are commonly asked how we know that you sent a payment. The address above was newly generated just for you, so when any BTC is sent to it, we will know to credit it to your account. It is all automatic.
https://bitcointalk.org/index.php?action=credit;promote
