Equipment scam!

I am beyond livid to have gone on my credit today to see that I have a collection from equipment that was returned. In 2019 I moved and. A technician installed Cox paneramic WiFi. It never worked. I had three different technicians come out none of them could get my phone or WiFi to work with the new equipment so the last technician took the new equipment and connected my old modem taht I had had for the two years prior. I finally had working internet. He took the panoramic WiFi modem with him and I asked multiple times that he had taken the equipment off. I was charged for over two years for this modem monthly and every time I called asking why I was being charged for the modem I was told it wasn’t a modem charge but a service fee for my type of internet even though that is not what the bill said. I have many issues with Cox and the service I received, the terrible internet service and constant changes in priced of bills but this is about the equipment I returned and now am in collections over. I moved in July and you guys do not service my new address so I had to cancel my service after making it clear the boxes for my equipment needed to be sent to my new address they still got sent to my old address. I had to drive to get them and brought the boxes with all the equipment to UPS as I was instructed. All of the equipment was packaged and sent back yet for a month and a half I received calls from Cox. And every time I answered then to try and resolve this situation. Every time they called they had something different to say about the equipment. The first time I didn’t return a phone if which in ever had a working phone. Then next call I returned nothing and so on. The final call said I had two modems and only returned one for them to look up my technician visits and realize I did not have two modems. I spoke to the highest management I could get and after the 6th call was assured that this situation was taken care of. When I asked for some sort of verification or email saying this was resolved. I was told he was “not allowed to” so I trusted them and the calls stopped. I am now in collections over equipment that was returned. A 50 point drop to my credit over something that I returned! I am fed up with cox and the lying and steeling and god awful customer service. I have never had a straight answer about anything with over four years of service and I need this resolved. After going on google I see that this seems to be a common practice from Cox and I would like this dealt with once and for all.