Data still dissappearing?

About a month ago we phoned the call centre to enquire about our data that just seems to dissappear. The guy advised that we take in all our devices that we connect to the wifi so that the technicians can check that all auto updates are set to off. I checked personally that all the updates are set to off. But A week ago we went to Vodacom to have the IT guys check that all our automatic updates is indeed switched off. The techinician said that the updates are set to off and we shouldnt have a problem. Just about an hour ago once again we were informed that our 5gb data is depleted... How can this be..? This happens every single time and has been happening for a few months already. I do not see the use in staying with Vodacom anymore.