Billed for 8.95GB while not even using the phone

The itemised billing indicates that 8.95GB was used on my drive to work, even though I didn't have any navigation apps open and all my apps only auto update over wifi. I don't understand how it is physically possible to use 8.95GB in a single transaction, never mind while I was driving and nothing was downloading or updating on my phone!<br> The Vodacom call centre lady was insistent in telling me that it must be because my apps auto update using mobile data, even though I can clearly see on my screen that they don't.<br> Neither the accounts nor the data inquiries departments could answer how it happened or how long it would take to resolve.<br> I have now been told that it may take up to 7days just for someone to contact me from Vodacom to start the investigation. The only solution offered by the accounts department is to suspend my number, as otherwise I will be liable for any charges.<br> The only options offered to me are for me to be liable for further incorrect data charges or have my number suspended and not have a phone for who knows how long. I don't believe that either of these options are practical nor are considerate of the client.