Bad service and not giving accurate information and not willing to fix it

Vodacom led about the amount of money I will be paying for my laptop. When they called me they said it's 289 a month. Come end of the month they took 560 when I called and asked them the consultants tell me about insurance I didn't agree taking with them as I had gotten my own insurance company. They then couldn't explain the rest of the monies on their statement. I confronted them again on fb after I called spoke to a consultant... They I asked I send them a copy of the statement on their inbox. I did. They asked me several questions and I asked they call me and they told me they prefer I speak to them on the inbox. I wanted to explain to them what I agreed on. They refused and instead they said do I want the insurance to be cancelled. I told them I need them to explain how we got to 560 from 289. That was the last time I spoke to them. Woke up checked my emails and they sent me a statement again. No call no nothing.... So I asked what's the procedure to follow to canceling my contract no reply. This is the second month. I was then told the data I get I will be paying separately which I was not told.