There are various reasons why this may have happened but we suggest the following step. Firstly, check with your bank to ensure there are funds available to pay for your order. Secondly, check that your credit card information is valid and up-to-date. If you were recently issued a new card, some of the information may have changed. Please confirm your credit card type, number, and expiration date, and try again. Thirdly, check that your name and address match the name and address on your current credit card.