Telkom bad billing system

I would like to lay a complaint against telkom. When I first got my contact my billing information was correct but for the pass months I've been billed so much. I phoned in to telkom and the customer care provider tells me that I have been taking recurring data bundle and this is not the case I have never taken any bundles and now I'm being charged over 3500 for data I never even purchased on my contract. Where my contract all together 435 pm. And where I work we have uncapped wifi. So y will I take data if get enough from my contract and plus I'm never at home coz I work 6 days a week. I never use my data I get on my contract coz I'm on the wifi at my work. So I really don't no how they can charge me for data I never use plus they put off my contact coz telkom tells my me im in arrears every month I have a problem with my bill even when I pay the full amount they still put it off the I have to wait 2 to 3 weeks for the reconnection department to reconnect my account again. It's so sad I've been with telkom for years to get such service