Product: Debt collection

I had received a copy of my credit report to find a collection that I had never seen before. I got the address, the account number and the amount off my credit report. I attempted to send the company a letter to validate this alleged account and amount, as I certified the letter and sent it, it was sent back saying there was an invalid address. After several of weeks not thinking about it I get a call from someone I know and they sent me a voice mail that the company had called and left them stating my name and a proceeding that was going to take action in the county I live and it stated that in the county I live. After 5 times of them calling this person, the person I know finally got a hold of me and sent me the voice mail. I called the person that left the voicemail back and asked them who this company was and only told me XXXX and they were trying to get me to pay something from XXXX. I asked to speak to a supervisor because this account was bogus, the guy ( XXXX XXXX XXXX said okay that's fine I know what I am going to do with this matter anyways because I refused to talk to him and transferred me to XXXX, She got on the phone and I kept asking what this was about she talked down to me and after having to raise my voice because she wouldn't give me the information I needed she said I don't have to listen to this and hung up. I called back again XXXX transferred me and I got XXXX again she hung up on me again! I called XXXX 's line about 3 times he never picked up so I called on a blocked number and he picked up and transferred me to XXXX again, I asked to speak to her supervisor and she said no you can deal with me, I repeated it and she said the same thing then I asked her what the address of the company was she wouldn't tell me I asked 6 times. She said I would know because of the letters they sent I said I wouldn't be asking if I got them which I never did receive anything. She kept talking over me and wouldn't let me say a word I told her I want her name and employee id number she just said her name is XXXX wouldn't give me her employee id number or let me talk to anyone else and then I asked to send validation with a signature that this is mine which is required under the FDCPA if requested for a dispute and she said oh I will send validation with the person when we see you in court and she said she is going to forward this to the county I live in now and I told her its not mine and I said okay take me to court since your threatening it. After that I found the XXXX website and number and called them and they said the alleged account number they left on the voicemail was not valid and they do not have a XXXX who is a supervisor nor a XXXX XXXX who works for them, she asked for the telephone number and was going to report it to their legal team for using the XXXX name and they are not associated with it. After I got off phone I went onto my credit file found the original lender I called them and they said they sold the account to XXXX XXXX XXXX XXXX which was who I tried to send the letter to months earlier that got sent back. I asked her if they have any association with XXXX and she said no XXXX XXXX XXXX XXXX is who has the account now. So she gave me another address that is not being reported on my credit file and I sent them a certified letter over night to them. No one is showing me validation of evidence bearing my signature or that I have some legally binding contract with my signature on it to pay them this alleged amount which is {$2200.00}. I have not received any letters from anyone about this, they had refused to give me their address and threatened to take me to court after I asked for validation. I called back a few more times and every time it went to a voice mail and I called back one more time on a blocked number he told me to hold on and as soon as he did that he hung up on me yet again.