To dispute an invalid debt use this disputing debt sample letter. If you've fallen behind on your bills, especially credit cards, don't panic.Want to settle your debt? This letter is to inform you that the validity of this debt is disputed and it is written without prejudice. Crafting a debt settlement letter properly can help you get your creditors to accept your proposal. Learn how to write correctly one now. Keep the format and tone of the letter formal but polite. If a creditor has refused your offer of payment then you can use the Reconsider my pro-rata offer sample letter to ask them to reconsider. A debt settlement letter is a tool to negotiate with your creditors and settle your debt at a lump sum payment you're comfortable making. Because of this and because of unanticipated changes in the law, the Rural Law Center of New.