Product: Credit card or prepaid card

Hello, In XX/XX/XXXX I purchased three shelves from XXXX. When I called to purchase the shelves they advised that I would receive a XXXX dollar credit if I applied for their credit card. I applied for the credit card and was approved. My total charges for the items was {$260.00}. Two of the shelves purchased were {$99.00} and the other was {$79.00}. With the $ dollar promotion my total charges were around {$260.00} total. I made my first payment in XX/XX/XXXX of {$75.00}. ( PAYMENT WAS MADE ON TIME ) In XX/XX/XXXX I made a second payment. The second payment was the entire balance that was left on the card. This was {$180.00} and some off cents. On around XX/XX/XXXX I received a bill from XXXX in the amount of {$55.00} dollars advising that that was a flex payment that was due. I called the company and ended getting a supervisor named XXXX. He agreed that I payed all of the charges in full. He provided me with a complaint number XXXX. I recorded this conversation where he told me that the charges were not accurate and that after the complaint was reviewed they would remove them. He also stated that I would here something prior to XX/XX/XXXX when the Payment was due. XX/XX/XXXXt came and went. I received no letter from XXXX or the credit card company. On XX/XX/XXXX I received a new bill in the mail that not only included the previous {$55.00} dollar charge but I also included a XXXX dollar late fee for not paying the bill by XX/XX/XXXX. I called back XXXX and spoke to another supervisor who sang a different tune. He proceeded to tell me that these were late fees. My bill that I received in XX/XX/XXXX was for {$55.00} dollars and said it was for a remaining flex pay. Now he tells me that the bill I owe is actually for late fees. XXXX NOT TRUE ) I said " the charge you billing me Is for a late fee for a charge that is in dispute. Are you allowed to charge me a late fee for something in dispute? '' I then advised that I did not receive any communication on the dispute decision. He began to talk to me like I was an XXXX and told me that I need to follow up with my post office. I asked when was the letter sent out? He said " it was sent XX/XX/XXXX and it was received by your post office on XX/XX/XXXX ''. So again I say " ok, well that makes sense why it is n't here yet as this is a holiday weekend. Further, how can you charge me a late fee for an item in dispute where I have not even received a decision ''. He refused to listen to my logic any longer on how the charges are not vaild. He then said " ok, we can settle this if you pay {$24.00} dollars '' I say " If I pay {$24.00} ( WHICH I DONT OWE ) will this go away '' he says " yes ''. I said this {$24.00} dollars is my balance paid in full " he said yes ''. I paid the {$24.00} dollars as I realize they are not going to resolve this and I do not want this on my credit. 
My {$55.00} dollar bill in XX/XX/XXXXwhere i was told it was a flex pay went to now being a bill for late fees and then a late fee for a disputed amount. None of it makes any sense. I paid my balance in full in the beginning of XX/XX/XXXX. So I did not owe it and am now afraid that they are still going to send me another bill. They refuse to be reasonable and are nasty to me and make me feel stupid. I work for a very large bank and I know this is wrong. I know that if they have done this to me they are falsely charging other people and talking them in circles until they give up and pay charges they do not owe. I am at my wits end and it is wrong what they are doing.

As I said above I have a recording of the first supervisor I spoke to in XX/XX/XXXX telling me I paid them in full and I do not owe anything else and then I receive a late payment fee for a charge I did n't owe. 

Please help me get to the bottom of these horrible billing practices. I am a consumer who needs help getting to the bottom of this. 

I appreciate all of your time. 

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