Paying for non service

So I joined Top Security in July they have been out seven times since that date & the joke is my alarm still does not work. I have been paying for a service that does not exist when my alarm goes off no one comes rushing to my rescue they have replaced the battery 3 times but in fact it is the aerial that needs to be replaced. I speak to everyone & they send people after people to fix & nothing. I now totally give up. My next step is to legal action as no one seems to care.