<prompt> Human: Comcast is pursuing a debt that doesnt exist. My past roommate paid off the final bill for our 1-year lease with Comcast at the beginning of August, but accidentally made an extra payment of about 80 at the end of August. Shes shown me email notifications from BOA that list the exact amount and who she sent it to Comcast so Im confident that she actually paid them. Shes always been reliable and honest. According to her, once she realized that she wasnt supposed to make the extra 80 payment, she contacted them and got the transaction reversed.Fast forward about a month, I the actual Comcast account holder get a bill from Comcast listing the exact amount by which she overpaid. The charges are for other services. So it looks like they dont know why they think I owe them that money.Ive gotten debt collection calls from a credit agency, and about 2 weeks ago sent them a letter describing the situation regarding her extra payments, as well as copies of the email notifications which prove that she paid them in the first place. I just got a call today, which concerns me, because by now they must have received that letter. What more can I do to get them to leave me alone? In the letter I told them to verify the debt with Comcast, so I think Comcast must not have admitted their mistake.  <response>: Debt collectors dont get paid by straightening out the billing confusion between you and Comcast.Debt collectors get paid by getting you to send them money.Send the debt collectors a letter stating for them to cease their collection efforts immediately as you do not have a valid debt with Comcast and to never contact you again unless they can show proof of a valid debt or else you will consider their continued contacts illegal harassment and will contact the authorities. 