Product: Debt collection

National Credit Systems on behalf of XXXX XXXX XXXX is attempting to collect a debt in the amount of {$4100.00}. This debt amount is incorrect due to XXXX XXXX attempting to collect double rent. I broke the lease at XXXX XXXX due to mold growing in the apartment and the hot water being out for more than a week. Maintenance was not responsive and it was causing my families health to deteriorate. XXXX XXXX agreed and I paid a lease buyout fee. XXXX XXXX is denying this ever happened stating they dont have a lease buyout program. In addition to this, another tenant moved into the apartment the month after I left which was XX/XX/XXXX. My stepfather began working XXXX  at the apartment to help out and we both seen another family living in the unit that I previously resided in which was XXXX XXXX XXXX, XXXX XXXX. The apartment community is attempting to collect double rent on the same unit by charging me for the remainder of the lease and charging the individuals that occupied the unit after me which is against the law since the company mitigated their damages by me breaking the lease. I opened a dispute the collection agency on XX/XX/XXXX. The collection representative, XXXX XXXX advised me that they have 30 days to complete the dispute. There have been no updates as of XXXX XXXX. I spoke with Mr. XXXX on XX/XX/XXXX and he intentionally gave inaccurate and misleading information over the phone. He stated that there is no timeframe that they have to make a decision and that he can not give me a timeframe and then preceded to end the line mid conversation after I respectfully asked for the information from him. He denied me the information and update regarding my dispute and continued to speak over me when I asked for the information. After this issue, I received another email attempting to collect the debt before the dispute is closed. The company also collected {$1200.00} from me at the beginning of the dispute because they stated it made my word more liable and that they determination would sway in my direction. I was unaware that debt collection agencies should not attempt to collect debt if there is a dispute in process. This has been a very stressful and emotional process due to me being in the process of trying to find a home. I was denied an application due to this incorrect reporting and the collection agency has been reluctant to process this information in a timely manner as required by law. In addition, I opened a dispute with XXXX and they closed the dispute prior to the collection agency closing their dispute. I am not sure how XXXX could validate the debt prior to the collection agency validating the debt with the creditor and the deadline for XXXX to make a decision did not approach before the collection agencys deadline. The biggest issue is the fact the collection agency is attempting to collect double rent instead of accurately updating my file. They are not following debt collection laws by continuing to attempt to collect debt while it is in dispute. The collection representative XXXX XXXX was very rude over the phone when I was nothing but, polite and understanding. He was not willing to listen and became very aggressive over the phone when I just wanted to get information pertaining to my credit.