Here are some reasons why your card might be denied:
1. Your credit card company, for whatever reason, has deemed that there are not enough funds or too many transactions on your account to process this order. You will need to contact your credit card or issuing bank to see why this is happening.
2. The credit card information you entered did not pass our Billing Address Verification Check. When we check a card for available funds, we also check to make sure that the billing address on file with your bank matches what the user entered on our web site. This is one way that we protect our customers from fraud. If the billing address doesn't match, the order will get declined.