Fibre box keeps dropping line

I have an ongoing issue with my fibre line. Firstly I had to fight to get a new router from you guys then the fibre box was replaced, so all on site equipment is new. My line keeps dropping and I don't mean just slowing down, I'm mean, ZERO. Ever time I call in I say there is something wrong and all I get is it will be escalated. This has happened about 5 times in the last month and a half. I need to asknthe question, what am I paying for?