Charged for Sim card I did not order

I was phoned in January by Mr Price and offered a "free" simcard. I advised that I did not need one, I was assured that I did not have to use it and that it was free. I recently looked at my statements, and not only was I charged a R100 rand connection fee, but have been charged R100 a month for a top up since January, thats R800 which I have been billed without my approval. I have been falsely led into accepting a free sim card, which as I have said I do not use. I feel that I am being ********** and sold something firstly I did not need and secondly was **** to about.