Airg Social services

I have become highly suspicious about vodacom of late when it comes to their billing. I got a bill of R170 for vlive (no clue what this is on itemised billing) in the beginning of the month which I was informed was for out of bundle data. Now the thing that has made me very angry is that I got an sms on the 5/04/15 saying \Your recurring R7.00 Subscription to AirG Social Service will be billed on 2015-04-07. To unsubscribe click [URL Removed] :)". I clicked on unsubscribe and found I had a 1 week free trial on my accound after which I would be billed R7 per week!!! I have never in my life heard of airg nor subscribed to anything via my phone. How does this happen vodacom? I am a student and I really don't need big corporate companies taking away money I barely have. So how does it happen that I can subscribe to a service I have never heard of? I am a highly suspicious customer at the moment."""