No Service

I have been paying for a few months now for a 1GB Fibre account and not getting that. I am only getting 300mb/s. I have been trying now for weeks to get hold of technical but without prevail. I have been holding on for almost an hour everyday and no success. Whatsapp have no response so how can a person get service from a company that doesn't even answer there phones??? Please make sure when you sign up with an ISP that they have the back up service when you need it !!!