Breach of contract

I have a system that I purchased and have been try for over 16 months to get a technician to come to my house to rectify problems that have been affecting the proformance of my alarm for more than 12 months but yet they arrive and demand entrance into my house without me being here. Saying to my **** that they have to get in to fix the problem but don't even know the problem and trying to get a manager to talk to about it is a nightmare no one wants to take responsibility. Again today I spent 20 mins with the call centre to be told it's my fault. Really where has customer services gone too. I am a very unhappy customer and am a single mom with a seven year old who does not feel safe even with a response alarm company.