Data charges

How can one proof that you didn't use so much data? Not once have I used so much on the account now all of the sudden over R2300 for DATA???. This is not possible. And then we got high billing on both cellphone numbers also for data usage. I feel that this is a easy way for Vodacom to make extra money as there is no way for us to proof this and then I didn't receive an sms to say out of data rates apply? <br> <br> Is Vodacom charging everyone for high data usage to pay for December bonus? <br> <br> I feel ********** and I cant do anything about this. I am cancelling all contracts possible with Vodacom.