Poor customer service and faulty censir

I regret installing Fidelity ADT alarm system in my house. The passed 4 months have been a nightmare. Alarm will go off anytime of the day and night without being triggered. We can’t sleep peacefully at night or even work freely during the day. I told them several times. They finally sent the technician to change the censor in the kitchen. It was ok for two weeks then started again. Everyday when armed it triggers around 11pm until around 2pm. To make matters worse they charged me separately for many times the alarm went off because of their error. They promised to refund me but still haven’t. I truly regret choosing ADT