How to use the template: 1. In the sample letter, fill in your personal information.This e-book provides templates for 21 most effective credit and collection letters that will help you communicate better with your customer. How do I fill this out? Use this letter to dispute an incorrect charge on your credit card bill. For best results, send this letter within 60 days after receiving the first statement. Our letter templates are your go-to pals for setting up, canceling, or sorting out any issues with creditors, credit bureaus, credit card companies, lenders. You will see credit letter samples that we offer and all are downloadable. Keep a record of who you spoke with and when — then follow up with a letter like the sample below. Many card companies let you submit disputes online.