Product: Debt collection

I was apart of a 3 person lease agreement on XX/XX/XXXX. The lease was from XX/XX/XXXX thruXX/XX/XXXX. During that time, I was called to XXXX duty from XX/XX/XXXX thru XX/XX/XXXX. Because of this, I was going to be let out of my lease according to the SCRA ( Servicemembers Civil Relief Act ). I let my landlord know of this  departure on XX/XX/XXXX that I was moving out on XX/XX/XXXX. I gave the landlord more than 60 days notice. When I received my official orders, I gave her a copy along with a document with her signature on it saying that she received the documents and that she would be agreeing to comply with the separation from the leasing agreement on XX/XX/XXXX. The other 2 residents stayed on the contract and found another person to take up my part of the rent. 
Once I got back from training, there was a debt from the apartment complex on my credit. When I looked further into it, the debt was put on my credit on XX/XX/XXXX and first reported in XX/XX/XXXX. I was confused and tried to call the XXXX apartment complex who kept giving me the run around. I then called the debt collecting company who now owed the debt, National Credit Systems, who not only was very rude and tried to coerce me into saying the debt was valid and belonged to me ( I have the phone call recordings & dates/times from my phone company ), but they refused to give me any solid information regarding it besides the first and last page of the lease. They refused to give me copies of the ENTIRE lease agreement when asked if I could retrieve it in order to see why Im being charged this amount, but yet she was rude and hung up on me. According to the SIGNED lease agreement for the what if charges, there was no amount or anything put into that section. Also, on the move out statement, the balance as of XX/XX/XXXX was {$1700.00}. On this same exact statement, there was a lease to date of XX/XX/XXXX ( the ending date of the lease ) & a move out date of XX/XX/XXXX. As I continued to read the move-out statement, there was a rent charge on XX/XX/XXXX, a termination fee on XX/XX/XXXX, two more write off charges of {$1100.00} on XX/XX/XXXX, and a {$2200.00} write-off charge on XX/XX/XXXX. This made the balance show {$0.00}. So when I called National Credit Systems for the last time to get clarity as to what exactly was going on, they got hostile again & told me nothing. ( Once again, I have recorded calls if needed ). When I finally got in contact with my ex-roommate, they said that they spoke with the landlord and asked if the TWO of them could stay another week past the lease until the new apartment was ready. They reached a verbal agreement and was allowed to stay. There was no new agreement signed with all three original signatures or anything of the sort. So these charges are invalid. 
Second, Once the landlord signed the paper saying that she was going to allow me out of the lease for military reasons, this shouldnt be present on my credit report as I was not here during those months and their new roommate gave money orders to pay for rent with their name on it to the landlord which further proves my case. I have documentation of everything stated in here and would like this removed due to it being a liability issue on my credit and its affecting my life. If this doesnt work, I will be forced to go the Attorney Generals office with the other two to show them that I was not present in the household during this lease let alone that I shouldve even been charged with this in the first place.