[Your Name] [Your Address] [City, State, ZIP] [Email Address] [Phone Number] [Date] [Recipient's Name] [Recipient's Address] [City, State, ZIP] Subject: Request for Refund of Duplicate Payment Dear [Recipient's Name], I hope this letter finds you in good health. I am writing this letter to bring to your attention a duplicate payment that was mistakenly made to your company. I kindly request your immediate attention and prompt action to issue a refund for the duplicated amount. Furthermore, I recently reviewed my financial records and noticed that I inadvertently made duplicate payment for [service/product] on [date]. The payment was made through [payment method, e.g., check, credit card, online transfer] and the transaction reference number for both payments is [transaction reference number]. Upon realizing this error, I immediately realized the need to rectify the situation by requesting a refund for the duplicate payment. Enclosed with this letter are copies of the payment receipts which clearly indicate the duplication. As per your company's refund policy, I am entitled to a full refund of the duplicate payment amount, which totals [dollar amount]. I kindly request that this refund be processed as soon as possible and that the amount be credited back to my [payment method/account] within [specified time frame, e.g., 7-10 business days]. I understand that mistakes can happen, and I appreciate your understanding in promptly addressing this matter. Your cooperation and swift action to resolve this issue will be highly appreciated, as it will help maintain the good rapport that I have always had with your company. In case of any clarifications or further information required, please feel free to contact me at [phone number] or via email at [email address]. I would be more than willing to provide any additional documentation or details necessary to expedite the refund process. Thank you for your attention to this matter, and I look forward to a prompt resolution. I have always been a satisfied customer of your company, and I trust that this issue will be resolved in a timely and efficient manner. Yours sincerely, [Your Name]