Telkom overcharging

I upgraded to telkom unlimited home 20mb fibre plan for R1008 per month. Telkom has been overcharging me substantially ever since. And charged me 3 times for a litbox that was free. I jabe calculated that i am also being charged R800 extra for the line as it seems the sales team messed up mu account. I have called into the billing department 5 times to fix the problem but no one knows what they are doing. Every time you call you have to wait 1 week for anything to happen. They have now suspended my account. I cannot afford to pay the R3000 they overcharged me.