Data gone in minutes

I purchased over 400mbs of data earlier today, 100mbs, 100mbs then 250mbs, all purchased in the space of 10 minutes and depleted even faster than this.. all while putting petrol in my car and driving. None of my apps were open or in use, so I need to know how this is possible. I then purchased 1GB worth of data which was clearly to much to be on 0mbs as fast as the previous data bought. Vodacom’s agents will always ask u the brand of your phone and let you know how much data your phone uses,, that’s there ‘comeback’ on being told vodacom just ‘took my data’ I have been with vodacom for years and when ridiculous is **************** then it’s really worth raising an eyebrow. I want to know how I will be compensated for the ‘lost’ data.