Telkom - Telkom steels your money and dont supply service

Since July I have been struggling with Telkom and their shitty service, I just wanted to change a debit order date, but Now they debt wrong dates and amounts and I have been double debited, and my service is still suspended, I don't know what to do as I use this contract for work and now I am in trouble about this as well, I cont get through to the right department, every time i request a call back probably 50 and I'm still waiting for one person to phone me back