If you think you have overpaid your Property Tax bill, you can contact the Finance. Department at (912)729‐5613 to see if you are entitled to a refund.You get an overpayment credit when your tax payments exceed what you owe. Sign up for reminders. Pay.gov is a free service that allows you to pay many, but not all, United States government agencies. Find the form you have been directed to use below. This guide explains what a tax credit overpayment is and ways to deal with an overpayment.