I received a bill in the mail. I go to the website to make a payment. I follow the exact steps the way Riverbank's guide shows (on FaceBook). I enter the Bill # and the license plate number appearing on the bill. The website comes back with an error (invalid account), so I can't make the payment online. If your bill is correct, your payment identification should work correctly. PS you have my proof of purchase, just look up my bill (bill # *******)