Postback error occurs when adding a payment account.
This is due to an error in the address of the information being entered. It is recommended to check the address, and/or manually entering in the information to avoid this. Also this error can be caused by the name on the card including symbols as well. Notably, if the user is typing in the name with an & symbol (ex: Smith & Smith), the site will need to have the data entered as "Smith and Smith" for the information to save successfully. Using a browser autofill can cause the wrong address being entered into the payment form.