Sorry I didn't tell you but unless the return is rejected you are stuck ... nothing can be changed after the return has been accepted not even the payment structure. Once you submit the return it is sent to a third party holding server where nothing can be taken back ... it's just like putting a letter in the mail box, no matter how much you plead the postman cannot just give it back to you. This is a security feature that is not working in your favor. Could you imagine what would happen if that holding server had a back door ? It would be such easy pickings for the hackers.
