These FAQs outline how to respond to an overpayment letter and provide guidance on next steps. Over Payment Refund Letter To Customers Template.You can also reach out to our Phoenix team through the Contact Us form and select the option "Phoenix – Overpayments. In this article, we'll show you how to write a refund request letter template that not only grabs attention but also persuades companies to act in your favor. To request a compromise of your overpayment, review this Compromise Request Form, sign and return it to the DES. You request they provide you with a reconciliation of your pay file to demonstrate you have been overpaid the amount at issue. The original permittee must make written application no later than 180 days after the date of the fee payment.