SAMPLE - REQUEST FOR REFUND OF DUPLICATE PAYMENT

On     [date]    , this office mailed to you a check in the amount of $       per your     [date]  invoice.

After reviewing your file, I realized that this account had been paid in full on    [date]       I am enclosing a photostat of our cancelled check #      in the amount of $[AMOUNT]

I would appreciate it if you would reimburse this office for the duplicate payment.  I apologize for any inconvenience this error has caused.

Thank you for your prompt attention to this matter.