Report the Collection Agency to the CFPB. In lieu of the Excise Tax bonding requirements this template may be used to request a Letter of Credit from your financial institution.1. In the sample letter, fill in your personal information. A letter of credit shall be worded as follows, except that instructions in brackets are to be replaced with the relevant information and the brackets deleted. You're saying: "Tell me more about this debt. " Use the sample letter on the next page to ask for more information about this debt. Mortgage lenders might request a letter of explanation for various red flags that come up in underwriting. Learn how to write one, and download a template. Also fill out the certificate of service with the date on which you intend to mail a copy to the opposing side and sign it. The certificate of service is.