Product: Debt collection

I have been moved from XXXX XXXX  for 7 months now. Lease ended XXXX of XXXX. In XXXX I had already moved on to new apartments and never heard anything back about a deposit or anything. I contacted the assistant manager of the complex and asked about my deposit and I was assured that I would receive something back in 45 days and never heard anything back so I let it go although Florida law states the consumer has 60 days to get their deposit back or at least notification of why they are not. All bills were paid before moving out and a cashier 's check was given to cover the last month 's rent since it showing the wrong amount in the payment portal. So there should have been a balance of XXXX. 6 months later, at the end of XXXX around the XXXX, this year I get a notification from XXXX  XXXX  that I have been put into collections through National Credit Systems by XXXX XXXX for XXXX dollars. Never received any notice of any payments owed or anything about me about to be put in collections by this agency also. My credit took a 79 point drop and I have never had any derogatory marks or problems in the past or problems fulfilling payments. I filed disputes with both XXXX  and XXXX  and they claim the dispute was closed because this National Credit System company proved that I was me ( Which was never an issue ) and that they supposedly proved they sent me something ( Never received any mail from them or phone calls ) ; so I assume they typed up documentation and sent it to the credit bureaus with false information that never made it's way to me. I have evidence of them lying about a date which I will attach later and have edited out address to cover personal info as prompted in case this is posted. After getting this result I spoke with an XXXX  representative who then suggested me to contact the company which I didn't understand why because this company is trying to get money from people so of course they would not work with me. I tried to contact them on XX/XX/XXXX but they were closed so I called on XX/XX/XXXX and left a message and then received a call back from a manager who then transferred me to a representative ( XXXX XXXX ). I explained the situation about how I never even received notification of this supposed debt from the apartments or the collection agency and I do not agree with these charges or collection. She spoke with attitude and said that they sent me something in the mail and called me. She then read me my address and phone number and I was able to confirm that information was correct so there should have been no problems with me receiving it if they sent it. She then proceeded to tell me that I could just take them to court to solve it or basically pay the balance. She also asked me if I wanted to be sent the notice in the mail and I told her she could send it if she wanted to but it still was never sent to me prior nor was I notified by phone and I said that my XXXX  XXXX  calls and records can be pulled if needed to prove they never called me. ( If they called me like they are claiming they could have even left a voicemail to prove ) Yesterday on XX/XX/XXXX the same day all of this conversation happened I receive the expedited letter in the mail. It is evident that this was sent to cover the collection company 's behind because the date on the letter was changed to XX/XX/XXXX which I don't understand why that date would matter as it has no significance to the issue and still does not meet the 60 day mark addressed in the Florida law. i have been wrongfully put into collections and was not even given the opportunity to know beforehand or dispute with the company and then when I tried to address the issue with the company I get met with disrespect, deception, and attitude.