Subscription without my consent

I received an account with an unknown subscription fee "vodalive" of over R300. I went to the local Vodashop to enquire about it. They logged a call and promised to cancel the subscription. According to them it was not a Vodacom thing and gave me an e-mail address which did not exist. To my surprise, the subscription is on my account again this month. Back to Vodashop where they only logged another call. This is unacceptable! I have to waste my time, energy and money to sort out something that I didn't ask for in the first place!