Fibre Line Erratic and Issue has gone on unresolved for a while now

Fiber line is erratic i have reporting this since last year !!! have putt may support requests this year and my problem has not been resolved and I constantly have to reboot my router at least 3 times daily. When I was moved from ADSL they told me it would be stable and there will be no such breaks sometimes its over the whole night its behavior is that of an ADSL line may i have this resolved quickly please Support takes days to respond to my requests sometimes doesn't even reply.