Auto Page Data billing

In April I received an account for R2848.31 for data used. I had the account for about 3 years and never used more than the 2 gig data on my contract. I had such a shock and hardly used the simcard with modem in May. My May account was for R2115.23 for data used. I logged about 15 complaints with Auto Page. I logged complaints with Worcester branch as well. I asked them to block my simcard. I returned tha payments for April and May and only paid my usual account amount. On my June account there is calls billed on that simcard!!! How is that possible. I also asked to make it a top-up (wich has been done) I am sure if that as not been done I would have get another huge invoice for data... I have been waiting for more than 2 months for Auto Page to supply me with the itimised billing. It is a MTN simcard and they said MTN have been on strike and I have to wait for the information. Now I have been handed over ! My phone (which is on separate account) have been blocked since June. I am more than willing to pay the money if the fault is on my side. How can they expect me to just pay without giving me any proof???? Worcester branch also cant give me answers!! T