Product: Debt collection

On XX/XX/XXXX at XXXX as I was driving home from work and I received an unexpected call from a man in which I did not get his name as I was driving- he stated I owed money from XXXX XXXX XXXX XXXX XXXX XXXX XXXX kept my security deposit and never sent me a final itemized deduction letter as to what I owed. I was forced to move out after living there only XXXX month due to the undisclosed cockroach infestation that the apartment had. They rented out my apartment XXXX month after I left, so it was my understanding that I only owed for XXXX month of rent which was approx {$1100.00} minus the {$500.00} security deposit that they kept ) the man stated an amount I can not verify because I was driving, but I believe it was well into the $ 2000+ range in which I explained I do not agree with that amount as I believe what I owed was approximately {$2000.00} less than the amount he stated. I told him I do not agree with the number he gave me and that I dispute those charges. He then became aggressive and said " Fine then I will note it as refusal to pay '' and hung up on me. 
That night on XX/XX/XXXX after going home, I looked online into " what to do when you don't agree with a debt owed '' and came across an article that stated that legally, I must receive a validation letter from the debt collector within 10 days of their first contact with me ( phone call XX/XX/XXXX ) or I can request XXXX from them by asking for the debt collector 's mailing address and sending the request via postal mail. 
The next day XX/XX/XXXX I called back the number for the debt collector, ( Cell phone screen shots showing calls attached ) which I now know as IQ Data International Inc. when the person answered, I stated that I was calling to get my account number and company address, in which she then transferred me to an unknown extension. A man answered and I said " Hi I received a call yesterday and I'm calling for my account number and your company 's address. '' The man verified who I was and repeated information from the day before XXXX XXXX being the debtor and I told him I understood who it was from and that I just wanted the company 's address and my account number. He proceeded to tell me I am being rude when I told him i was not, and I was just looking for my account number and company address. After speaking over me a few more times telling me I was rude and telling me he was going to hang up on me, I kept asking nicely to please give me my information, the man hung up on me. I then called back from my work phone in which I had to give them my phone number to verify my account. When that man asked why I was calling, I told him how I was looking for my account number and the company address and that i just called and the man I previously talked to called me rude and hung up on me- this man then hung up on me as well. I called back again from my work phone and it just rang. I was unable to obtain my account number with IQ Data International Inc. or the company 's address. After searching online, I found XXXX different addresses for the company. Including two po box es. 
On XX/XX/XXXX I printed and filled out XXXX copies of a form requesting validation of debt from IQ Data International Inc. ( Attached ). 
I had the letters notarized and sent all three copies via certified mail the same day on XX/XX/XXXX to all three addresses ( Receipts attached showing the tracking and that they were all signed for on XX/XX/XXXX ) I never did receive any type of letter or any correspondence from IQ Data International Inc. after their initial contact on XX/XX/XXXX or after receiving and signing for my request on XX/XX/XXXX as stated under the Fair Debt Collection Practice Act ( FDCPA ) in which IQ Data International Inc. is in violation. 
Today is XXXX 29 days from IQ Data International Inc. 's initial call to me and 22 days from when they received my request for a validation of debt and I still have not received any correspondence from them. This morning XX/XX/XXXX at XXXX I receive an email from XXXX XXXX that IQ Data International inc. has reported a collection/chargeoff on my credit. ( attached ) Again with no letter of validation of debt, no other communication, not even via phone, no account number, no notification of why they say I owe the balance they claim, not formal way to dispute it and no opportunity to pay anything at all towards the balance I believe is actually owed. How can I properly or legally dispute a debt, or even pay a debt if the company, IQ Data International Inc. will not give me the opportunity or will not give me further information and hangs up on me and doesn't even respond as they legally should, to a notarized, certified and signed for letter via the postal office? This is unfair. It is a violation of the collection practices act for a debt collector to refuse to send a validation notice or fail to respond to my request for a validation letter. By filing this complaint, this is the first step out of as many possible that I have to do to properly and legally rectify this issue. I did everything I was supposed to do and in return have been violated against. Thank you very much for your time as I know this was lengthy. 
XXXX XXXX XXXX