<prompt> Human: This is a follow-up of sorts to my previous post where I thought everything had been resolvedIn yesterdays mail I received a collection notice from Grant Mercantile Agency is IDing them by name okay? Ill remove their name if Mods disapprove showing a Principal amount of 0.00, because Id paid the bill in full in June, but with Interest of 15.38. So the collection agency is claiming I currently owe them 15.38. Because of interest and other charges that may vary from day to day, the amount due on the day you pay may be greater.I immediately called the radiology center where Id paid the bill in June but their AR people had already left for the day, so I got ARs direct number and am planning to call them this morning.Im hoping AR will call the collection agency CA and tell them to knock it off.But its also entirely possible that this is something I may need to do myself.So, thats the question.If I do have to call the CA myself and IF theyre not willing to acknowledge that this is clearly a computer error and just zero out the account, how do I fight this? What do I tell them? Other than fuck off, you shady cunts. Because that would not only not be polite but counterproductive as well.And Im certainly not paying interest on a bill that Ive already paid in full.Update: I just spoke to AR, told them the CA was charging me 15 interest on a 0.00 bill, and they agreed that thats not right. Theyre going to send me a 0.00 statement, and said they will also contact the CA to let them know the account has been settled. I guess Ill have to wait to see if the CA is willing to play ball, or if theyll still try to get a slice of my pie.2nd Update: A couple of hours have passed and I decided to call the CA myself. With all the bad rep CAs get, the lady I spoke to was very polite, friendly, nice, etc. She looked up my account, told me it had been zeroed out, and that I did not owe them a penny. She also assured me that the debt had not been reported to the credit reporting agencies, then reassured me a second time that it would not be. Yes, she actually said it twice, that it has not been reported and will not be reported to them.Due to the security snafu with Experian we have their Pro service for a year or however long it is so when I get home tonight I should be able to pull my credit report with them for free, regardless of the one free report per year caveat.Assistant: Do you have a receipt for the date of the payment? On the statement does it show the dates that the interest has been accruing? Human: I have a statement from the radiology center dated June 19, 2018, which has charges for the two x-rays totaling 234 but says nothing about interest.I have a receipt for the payment I made on June 22, and I confirmed with the office staff at the time I paid that it was now paid in full, because the receipt doesnt say paid in full. I was concerned about this because they were reducing the bill from 234 to 140 because that was the price they charged to someone without insurance. I have insurance but it wasnt accepted, see my original post.The statement from the collection agency does not indicate how long the interest has been accruing for. Ive posted a copy of the bill from the collection agency on Imgur. Ive redacted my personal information but if somebody really wanted to Im sure they could find me.  <response>: Sounds like they had already sent it to collection from missed payments and from that date they were charging interest. 