The most common reasons for a payment to fail is that the credit card on file has expired or does not have enough funds to cover the charge.
First off, you will need to sign into your BDOW! account and sign into the billing portal.
Once you are signed into your billing portal you can change your credit card information.
Once you get to the Edit Payment Information page, you will simply fill in all of the information requested and click on the Save button. Then you are all set!