<prompt> Human: I checked my mail today to find that the apartment complex I moved out of two years ago Fall, 2011 has sent a debt in my name to a collections agency. When I moved out, they claimed that I did not sufficiently clean the apartment, and charged me 60 for a cleaning service to come in and finish the job.Well, the whole reason I had for moving out was because I had lost my job and was broke, so I couldnt pay the debt right away. A few months later, I had a new job, and I came into the office and paid via check. Sometime in 2012That was the last I thought of this until today, when I received the notice that the apartment complex had sent my debt to collections. I called the office contact number and they told me that the debt was in relation to the cleaning charge.I told her that I was confident that I already paid this debt, and she informed me that I would need to provide proof, otherwise they put a mark on my credit report. I told her that I was disputing the debt, and she said that I would be unable to do so until I provided that proof.I assume that I requested a receipt when I paid the debt, but I honestly cant remember with certainty that I did. I have checked through my files, and I dont see anything along those lines. Its also completely possible that I came across the receipt and threw it out months later because I wasnt expecting anything like this.Unfortunately, the bank account that I sent the check with has since been closed, so I cant just pop online and check past statements to see if there was an appropriate charge. I understand that I can go in person to a bank branch and request and possibly pay for a historical report, but from what I read on this website: it sounds like I am not legally required to do so. If it seems like a good idea, I will, but I wanted to check around first.So, it sounds like the first step I need to take is to send them a written request for proof of debt. Is this something I can do at the same time that I formally dispute the debt? Is there any truth to her claim that I need proof that I already paid it?Ive written up a quick summary of the conversation I had with the collections agent. I will make sure to document any conversations I have with them, and make copies of any letters I send them.If it matters, I received one bill from the complex informing me of the cleaning charge, soon after I moved out. To my knowledge, they made no other attempt to inform me of the charge. When I paid the bill, I did so in good will, and without them hounding me for it. I received no other notices of the supposed debt until today.  <response>: All you can do is show a cancelled check, unless you want to go to court over the matter of even having the debt at all. Youve stated you closed that account, I really hope you saved your registers and old checks. If not, do so from now on. 