Suspicious data charge no response

I've incurred a massive data charge on Vodacom of almost R4000 and requested an itemised bill. After that I logged a service request on Tuesday to try and figure out how this is possible, and Vodacom told me someone will get back to me within 24-48 hours. After 48 hours I called them back on Thursday to follow up and they can't tell me what's wrong as Customer 3D is offline. Today I called again, but still no response.<br> <br> Surely if you want to charge me for something you should be able to explain what is was for.<br> <br> Vodacom please sort this out, and please migrate me back from Customer 3D as I've consistently had issues since I've been migrated. <br> <br> At this level of service, I'm seriously considering cancelling my contract with Vodacom.