Product: Debt collection

My lease agreement was not renewed, and I notified the property manager about moving out on XX/XX/XXXX of XXXX. I was informed by the property manager that I will still be responsible for the whole month of XXXX and the total amount for the rent was {$1200.00}. In XX/XX/XXXX of XXXX I sent a partial of {$680.00} and in XX/XX/XXXX of XXXX I received a letter from the property manager of XXXX about my remaining balance for the month of XXXX, the letter clearly states that the total amount owed was {$750.00}. I returned my apartment keys on XX/XX/XXXX of XXXX, I also let them know about my new address. I received a call from Rentdebt collection agency around XX/XX/XXXX, informing me about my rent debt they were trying to collect on behalf on XXXX. I requested a breakdown of the total amount since they told me it was over {$2000.00}. l explained to them, that the amount sent to them by XXXX was incorrect and they should contact the property manager explaining that my knowledge of the total amount owed was different. I was told by the collection agency representative to wait at least a month to hear back from them. I called them again in XXXX of XXXX and spoke with XXXX, who informed that the property manager has not yet responded, and that she will reach out again after hanging up with me and for me to call back in 15 days. I called the collection agency again the first week of XX/XX/XXXX, spoke with XXXX again who then told me to send her an email including the letter from XXXX dated XX/XX/XXXX with shows the total amount owed was {$750.00} and also attached the partial payment submitted by me on XX/XX/XXXX. I sent the email with everything as she requested on XX/XX/XXXX and waited to hear back from them. I called the collection agency again in XXXX of XXXX and was told that they still haven't received a response from XXXX property manager. I called the collection agency again in XXXX of XXXX and was told again that they did not receive a response from XXXX property manager. Finally on XX/XX/XXXX of XXXX after waiting to hear back from the collection agency, I called once again and spoke with XXXX who told me then that they received my email, but they were unable to open one or more of the attachments. I sent her again another email on XX/XX/XXXX including all the attachments and waited to hear back from them. I called the collection agency again in XX/XX/XXXX of XXXX and spoke with XXXX who told me that they have contacted the property manager XXXX XXXX XXXX and he confirmed that the amount sent to collection was correct. After that call, I immediately called XXXX and spoke with XXXX the manager, who then inform me that nobody from the collection agency have reached out to him requesting to correct my information. He then preceded to access my account and inform me that he found the reason why the amount sent to collection and the amount actually owed were different and it was because the rent and parking expenses were charged twice on my account. He was going to send an email to the collection agency stating the correct amount owed by me which was {$750.00}. I told him that I've been trying to pay but the collection agency refused to time and time again to investigate or try to reach out to him about my dispute. I was promised by XXXX the property manager that I was going to receive a call from the collection agency soon. After waiting for two weeks, I called XXXX again and spoke with XXXX the property manager who told me, he sent an email back in XX/XX/XXXX to the collection agency. I informed XXXX that now this whole situation is affecting my credit and also let him know that I have applied for an apartment and my application was denied due to the credit report about my debt with XXXX. It's unfair that I have been trying to resolve this issue for many months calling, emailing and nothing have been resolved. He says he will again send an email with the correct amount owed to the collection agency and I should receive a call from the agency soon. Today is XX/XX/XXXX and have not yet receive a call from neither the collection agency nor XXXX.