There are multiple reasons: Your credit / debit card has been declined. You may have exceeded your daily transaction limit, or the amount available on your credit / debit card. Alternatively, you may have entered an incorrect card number, expiration date or CVV code. Therefore, please verify that the above information is filled out correctly, and also make sure that your card has not expired within the validity period. Finally, verify with your card issuer that your credit card is authorized for online transactions and that nothing is preventing its use.