Vodacom - no resolution or interest in doing so

Over a year ago, I upgrade my children's data only account. I then found out that the accounts were on open lines I called through on more than one occasion to rectify. Which was supposedly done a year ago. My last call was almost 2 hours long to resolve. A year later I am hit with 4 bills in excess of R6k per month. When I called, again I was told that the changes were never made. There are charges for Apple that I have requested be investigated and have received zero help from Vodacom. I have ask it be investigated and in my last call was told I must go to Apple. I asked for a formal investigation into what has transpired. Call ended and I received a notification that the query was closed. I am now neing threatened with being handed over for R12000.