Vodacom upgrade to 36 month instead of 24 month

Initially I was very impressed that the consultant assisted me so well with the upgrade of my Vodacom contract. Unfortunately I realized today that I was "upgraded" to a 36 month contract despite me specifically asking the consultant if it was a 24 month contract and him confirming this more than once. I am now forced to spend time, which I don't to try and get this sorted out. It seems Vodacom can't sort it out immediately as the upgrade was done through a third party. By me agreeing to the terms and conditions(in which the consultant again confirmed the period to be 24 months) constitutes a legally binding contract, yet here I am struggling to get my contract sorted.