Vodacom bad service provider

I'm very unhappy with the service that I received from the vodacom call centre.In 2 days R200 worth of data and airtime disappeared from my account. When I called the call centre the agent said that I won't get my money back and its my fault because there are apps running in the background .I explained that all my apps are restricted and I don't download anything and I update all my apps over wi fi.She insisted its my phone that's the problem ...My question is how does my data disappear immediately after loading it and my signal on the network has also been very bad for the 2 days .I want to be reimbursed for all the money that I spent within two days and not having any use of my phone.