Blue Security - service lacking

This is not a reliable security company. They used to be good, but lately service and reaction has been badly lacking. On 4 occasions now I have phoned them and they have not answered the phone & it has rung off due to no answer. Last week this happened twice. I reported it and they said that they would deal with it. It happened again today. What is the point of paying a security company if they don't even answer their phone! Also, when my alarm is activated sometimes it takes from 5 - 15 minutes for them to phone me. Not acceptable! I had a cellular transmitter fitted last week in order to receive open & close notifications. I have complained that this was not working constantly for a week, it is still not working! useless service. I am looking for another security company, Blue Security is not reliable.