Daylight Robbery

I have purchased a property with a pre-fitted alarm system that I had signed a change over from the previous owner of 10 years. Within the first 3months of my change over I have had numerous complaints with this alarm system. For every call out by them, i was charged a huge fee only for their techs to tell me that the system is Obsolete, and they had to disconnect a few zones to make it work, the keypad itself could not be replaced. Nonetheless I did opt to cancel this company's services and get another. Mzanzi has charged me R11500.00(according to their lawyer) for fees under a year of their service. I was listed as a default for R1874 on my credit profile of which I paid in September 2021 after calling their offices and obtaining a "go ahead "from their debtors department. However now I get calls from their lawyer demanding more money to remove this from my ITC. I have cancelled their services and am now 2years with another provider but I now have to pay them for their pathetic services, which I don't think is fair to me. I need assistance for I cannot get credit anywhere with this Default on my name , of which is the only account I have.