Vodacom Fibre - connectivity is bad and no support available

Vodacom Fibre connectivity has been dropping consistently since we had it installed. Each time I contact the support centre they close the calls and insist nothing is wrong with our line. The wifi has been dropping consistently now since last Friday and has been down 90% of the time, yet come the end of the month I get charged the full price. I work from home and this is a nightmare. I can't even get through to the fibre support contact centre...