In the Create Request form choose Refund Request or Advance Aid under Request type. Complete the required fields and hit Submit.Clearly state the decision regarding the refund. Over Payment Refund Letter To Customers Template. Form TR210 is a letter you receive if: If you received it, you may be entitled to a refund for the tax year stated on the letter. • Collection of debts from your refund or overpayment. This brief but important letter notifies a customer that he or she has overpaid you. It can serve as a very good customer relations letter.