Axxess charging for no service

Axxess supp**** me with a new high speed fibre internet line. It took them 2 months to resolve the installation error on the cables, after they started charging me. My fibre internet did not work at all for that duration. I had to log numerous calls before they actually attended to the problem.

When I requested a credit for that period they responded that no credit will be given because they do not guarantee 100% service.

Surely 0% service due to their installation error should be treated differently.