Product: Debt collection

in XX/XX/XXXX, my contract with XXXX XXXX was about to expire and I was moving to a new address. When I notified XXXX XXXX that 1 ) i was moving, and 2 ) i would not be renewing the service, they did the following : a ) refused to move the service from the old address-XXXX XXXX XXXX, XXXX, and b ) refused to give authorization to return their equipment. Many unsuccessful phone calls followed in which I was transferred to different departments to try to get me to keep the service. I refused all, and they refused to acknowledge my request to return equipment. 1 year passed, fast forward to XXXX, and in XXXX of XXXX, I discovered that I could return the equipment via XXXX, which I did. I received email from XXXX   XXXX that the equipment was received, and that was that for me. I never got anything else from them. 
Fast forward to Saturday XX/XX/XXXX, I went to the XXXX XXXX XXXX store to make changes on my account ( i have been an XXXX XXXX XXXX customer for 25 plus years ) and was told no changes could be made because I owed some money, and I was given a number to call XXXX XXXX XXXX XXXX XXXX. I called the number because according to the customer service person at the XXXX XXXX XXXX store, XXXX XXXX had attached a XXXX $ plus bill to my account. 
So I called XXXX XXXX and got the run around. The first person I talked to refused to give me his name, told me he didnt have to, and said he could not help me, so i hung up. 
Next day, Sunday, the XXXX of XXXX I called again, and once more I got someone who listened to my inquiry, which was, why are you adding a bill to my XXXX XXXX XXXX bill? what is it for? 
This new person, who said his name was XXXX, told me that the account was in collections. I told him this was news to me, and I requested to speak to a supervisor. Another 20 minutes of being told I could not speak to a supervisor. But upon my insistence my number and a message was left. Then I hear absolutely nothing, so on Monday XX/XX/XXXX, I called XXXX XXXX again, and this time I got a girl who told me that my account was with a company called Credence and she gave me a number to call them. 
I called and got a fast talking guy, whose name I still do not understand. He told me that the charges were for early termination and an old bill. 
I told him I did not early terminate anything, that XXXX XXXX  refused to move my service when i moved, and then refused to take the equipment back. He verified that the equipment was back, and told me he sees that I am not at fault, and he would offer me a reduced payment of XXXX to go away. 
He wanted payment right away, and I told him I would consider his offer when I receive it in writing. He then transferred me to another fast talker who said he was a supervisor and said the same thing. I told him I wasn't agreeing to anything until I got it in writing. I verified they have my mailing address. I ended the call. On XX/XX/XXXX they called me again from a different number, XXXX seems it may be a voice over number, anyway the person wanted to know if I got their mail, no I had not. I told them when I get their mail I would contact them. I checked my mailbox every day and nothing. Today, XX/XX/XXXX, they called again from a different number XXXX and as soon as he identified where he was calling from, I told him I having no conversations with them until their offer is received in writing. I believe these people are not only harassing me, but hustling me for money I do not owe. 
I really want them off my XXXX XXXX XXXX account, and am really disappointed that XXXX XXXX XXXX told me they could not handle this issue since its XXXX XXXX. I am willing to pay them some fall amount to get them to go away, if nothing else works, but it is ridiculous that after 2 weeks, I got 1 call one day from XXXX XXXX XXXX, about a supervisor calling me back, but I could not talk as I was at work. I want this removed, cleared up, marked paid in full and taken off my XXXX XXXX XXXX  account as this was around before XXXX  XXXX XXXX and XXXX XXXX  connected, plus no one, no one at either company would tell me when they actually wrote me about this. 
They have sent me zero mails, and the only email I got was to acknowledge receipt of equipment returned in XXXX. I want this to go away 3 weeks ago.