Battling to get authentication although fibre is active.

I keep on losing authentication although my line stays on. What I mean by that is the on the ONT (Black Fibre Box), The broadband and service light are green, with the ethernet flashing. SO there is nothing fault with the fibre connection (frogfoot) but I can't connect to the internet. For my first 5 months I only had 2 occurrences where my internet went down for maximum 2 hours. Now I am struggling daily to get authentication. I tried 2 routers so I know the fault is at webafrica and not on a router or frogfoot.