incorrect amount being charged

a gentleman by the name of tshepo called me one morning and told me about a router that I could use in order to access internet and I was told I would receive 2MB a month and pay only R149 per month for that, and I agreed. the first debitborder that went off was for an amount of around R500, but I did not query that as I thought the amount might be including the monthly account fee since I took the contract in the middle of the month. so the second month cell C did not debit from my account and when a statement came for august it stated that actually have an outstanding amount of around R2000. I queried this and was told I was on an open plan(I don't know what that is) and I am getting R2000 including the 2mb that I get every month. I told the lady that I spoke to that I hqdvno idea about this open plan thing since it was not disclosed and I was told they would pull the call and listen to it, since then I have not received any feedback.