Being harassed to pay an account that I asked to be switched off

I am disgusted with ADT. Last year May I called ADT to switch off their service as I was renovating my house. Which means that I was not going to pay anything until I reinstated their services. A few months later I received a phone call informing me that they will be switching off my alarm as I was not paying anything on my account. I was furious and informed the consultant of what had transpired. He then tried to find out whether what I was telling him had merit. He informed me that it was written on the person's computer that I had initially spoken to, however, the alarm was never switched off. He then informed me that he was going to email her and ask her to call me back which she never did. I kept receiving account statements every month. I again called ADT and had to reiterate myself to every person that they kept sending me to. When you call their line, it states that their calls are recorded. I asked them to retrieve all the calls so that they can see if there is truth to my story. To my suprise, they informed me that not all the time their calls are recorded and that the person that initially helped me has resigned. I was assured that the manager is going to get back to me. No one has called me since. Instead, I am being harassed by their lawyers informing me that I should pay ADT money. How the hell has this became my fault after I have made numerous calls and informed them about the problem and now I have to pay for their consultant's incompetency.