Missing data

I highly regard Vodacom as the best network in SA. I have bee their client for about 15 years since varsity. I have a data contract with them of about 80gigs per month and for the 1st time ran out of data, when I normally carry over data to the next month. Now I checked the app and it shows that I have been using a lot of my data on an 'Ultra-surf App' and I used about 80 gigs on there. I don't have such an App. There are also downloads of over 50 gigs over the past 30 days, however I only download a few memes. Could it be possible that hackers are able to use the ultra surf app to bypass and access my data and make downloads?. Where is Vodacom's security features?. Please kindly rectify this security breach and credit back my ******/lost data. I lost about 60-80 gigs in the past 30 days because of this including the data that I carried over.