Vodacom data depletion 100gb

I’m complaining again about Vodacom data. How can I use 60 gb in less than a week? The consumption doesn’t make sense at all and when I try to cancel the contract, I’m told to pay a premature amount while I’m not happy. Spoke to consultants and they also were shocked of how in December data was flying. I used to carry over data to the next month but not anymore. I want to cancel this contract and I’m not willing to pay.