My contract was renewed without my consent

My contract that is expiring next month has been renewed without my cosent, I received a call on the 21st of August 2015 where a consultant told me that they will deduct R150 from my acc, I told him that I wanted to cancel the contract once the two years is over, he tahen said I can cancel it in September, when I called vodacom to cancel I was told that my contract has been renewed. I tried to call elite mobile but they are closed for training. I never asked for the contract to be renewed I specifically asked whem I will be able to cancle because I never used the tablet they Send me in 2013, it wasn't working. Please assist