<prompt> Human: I am a college student and am living in an apartment near campus. My dad really didnt want to co-sign a lease so when I signed my lease here I had to pay the full amount due for the whole ten months ,as a lump sum, in order to live there without a co-signer. The part that concerns me is that today I receive a call saying my rent is late, so I tell them that isnt possible since I already paid the whole sum and tell them Ill stop by the office after I take my last final. When I get there they realize that they made a mistake all the way 9-ish months back and charged me 330 less than they should have. I tried to dispute it saying it was their fault and that the contract has already been signed with the stated amount and paid in full, I even brought my copies and receipts to make sure our versions match and they did. I ended up paying because they were threatening to just keep my security deposit and still charge me for it. Thing is Im moving back home in a few days since the semester is over and Im wondering if I should have even paid. I really want to call VISA and get them to issue a charge-back but that probably wouldnt accomplish anything. Overall, I just have a very bad taste in my mouth from this whole situation and Im wondering if anyone has some insight on what I could have done bettercould do now.  <response>: I would definitely call VISA and have them not honor the payment. Then when they send you a disputed claims form you can provide your documentation. That company breached their contract and you are not liable for that 330. Call VISA and tell them that the 330 is unauthorized and you want them to not honor it. You only pay something like that when you dont have receipts and documentation, they basically just took advantage of you because you are a young college kid. 