They bill me for an alarm system that is not working

I have gotten this company to install an alarm system this was in October 2021, they were so unprofessional in managing time because I had started to engage with them in July, it took them 2 months to finally install the system but after they installed it it hasn't worked because it gives me 2 seconds to exit the house after alarming the system, I have called I have emailed to get this fixed since then, it is January 2022, I will start by reversing all the debits since October because I am paying for service I am not using.