Sample Letter of Credit in MS Word format. Use this sample letter to dispute incorrect or inaccurate information that a business supplied to credit bureaus.See a sample credit dispute letter below. Explore professionally designed credit letter templates that are customizable and free. Send out beautifully designed and printable letters. 1. In the sample letter, fill in your personal information. The next screen has several fields to fill out. If time is of the essence, follow up sooner. Appeal Letter Format. Please fill in the whole form in BLOCK CAPITALS using black or blue ink.