Fidelity ADT

I wanted a car tracker from Fidelity adt last year March 2020 and they have sent someone to install it during the month of March but I was never told that it's a trial and it will expire after one month even the guy who called me and explained how does this work before installing it he never told me that it's a trial. During the month of April 2020 I received an email saying that the tracker will expire month end of April and by then we were on lockdown level 5 so because I wanted it I rep**** on the email telling them to renew it and they told me that I need to call their support department. So after month end of April I couldn't access the app and I couldn't activate it so that my car can be protected and since then I couldn't use it till now I still can't use it. I have been receiving calls from this company saying that I owe them R2800 and now they have handed me over to the lawyers. And what's worse is that Johann Ntuli called me from the Fidelity company telling me that they have pulled out the telephone records and she agreed that I was never told about the trial so I thought she will fix it cause now she can see that the mistake was made from their side but I was wrong cause I have just received an email from the lawyers telling me that they want the payment with immediate effect or they will blacklist my name.