We first recommend logging into your account and confirming that the address in your profile is updated and accurate. You can check that here:
Also, clearing the temporary internet files (such as cookies) in your browser may provide a solution. To clear your cookies in most browsers, you can press Ctrl + Shift + Del at the same time on your keyboard on a PC, or Command + Shift + Del on a Mac.
For credit or debit card payments, please check to confirm that all of the card details you're entering are correct and current, including the address and security code. If you already have a saved credit card then you can try deleting and re-entering the credit card information. To do this, click the "Edit" text to the right of the "Paying With Card" header. You can delete the saved credit card by clicking the "X" in the red circle. Then, you can re-enter the credit card information.
If you're using PayPal to checkout then you may wish to check the source of funds and settings in the PayPal account.
If your card is a Visa gift card, we recommend registering your card for online use. Many gift cards have this option.
If the transaction is failing after repeated attempts, we recommend contacting your bank or financial institution to see if they can give you any information about the reason for the decline.