Data usage issue

1GB of data and all my airtime (which last me a full month usually) got completely drained within 8hrs on Sunday(2 Aug 2015). I went in to vodacom and basically got told it's not their problem, it's my phones fault(but all apps are switched off and closed). Now I refuse to spend more money on airtime cause it will just happen again and so am basically phoneless. It's happening to so many people aswell so vodacom must sort it out please!