1. In the sample letter, fill in your personal information. Expiration Date: Letter of Credit Number:.Our guide will teach you how to write a letter of explanation, plus offers a free template to help you write one of your own. A credit dispute letter includes personal information and enclosures that help credit bureaus investigate mistakes. Free downloadable letter examples to help you communicate with your bank and credit union account holders. Use this example below as a guide when writing to or talking with creditors. Replace the blanks with your own information. FindLaw provides a sample credit repair letter and outlines the common reasons a consumer would have for sending a letter to a creditor. Irrevocable Letter of Credit. Obtain a letter of credit application from the bank and fill it out with the relevant information.