No customer service ethics

I moved into my sister's house in July after she passed away. In September 2019 a consultant came to the house on my request to activate the alarm which was installed already. All was set and she done checks on the keypad. The contract was signed and the debit order was only suppose to go off on the 26 Nov 2019 for an amount of R712.00 ( the months fees of R350.00 plus the anniversary for the year of R362.00). I was informed that I would get the FIRST THREE MONTHS FREE. Two weeks after that a technician came out and for the life of me I don't know what he done to the system, but from that time I have bee receiving calls non stop ( about +20 calls a day). I even pulled out the plug but still received calls. He also said that he could fix the system for R1200.00 cash. I told him that even if I win the Lotto I will not get him back. I complained and two weeks ago a new technician came out and fixed everything in no time. The system was working but he did explain to me that the battery is low and in time I would need a new one.

I have also sent through e-mails requesting for them to change the second contact person in but to no vail. I spoke to Zinhlem and she said that I must e-mail the changes to her. Nothing has happened. They debited my account on the 26th October 2019 for an amount of R830.00. They have not got back to me since sending them an e-mail.

Sending me a contract of 2014 which my sister signed when she first took out the alarm system.

I am having second thoughts about this alarm system.