Deducting unauthorised subscription

Received messages that airG gold subscriptions are deducted from my account - how can anything be activated or deducted from my account without my authorisation !!! Please deactivate this with immediate effect! I called Vodacom (Ref ***) the operator clearly did not understand my concern & told me to go to a Vodacom store for assistance... What is the point of a customer service centre if you cant get assistance!