Have you sent them a certified stop calling letter yet? If not, that is the first step. If they continue to call after the letter is sent, write down the name of the creditor, the agent's name, the time and number of times that s/he has contacted and send that information to the Attorney General Consumer Protection Division of your state and file a formal complaint with the FTC. If after all that, they still continue to call, you must inform the caller that you will have to record the conversation so it will be forwarded to the AG Consumer Protection Division as evidence of your case. Good luck to you!