Not responding to inquiry

I bought a Laptop through MTN and was paying it off in instalments of R405 which they deducted via Debit Order every month. Last month all of a sudden they deducted an amount of R12603.30 from my Banking Acc. When I queried it, they told me that we used that amount of Data on the Internet. I then requested that they please send me the Statement and breakdown of my Account as I don't ever receive any Statement from them to show how much Data had been used. I only receive a Statement stating the amount that is supposed to be deducted every month. I kept phoning and sending e-mails for two weeks, pleading with them to please forward me the information as I will really not mind to pay if I can see what I am paying for. Every time I phoned during this period, I was told that they would forward me the information via e-mail within 48 hours as it takes 48 hours to generate a Statement on their side. I gave them my e-mail address as well as my wife's just in case they didn't come right with mine. Until this day I am still waiting for proof of the Data supposedly used. <br> <br>