Consultants committing ***** on clients accounts

I asked vodacom to cancel my contract they told me early termination will have to pay panalty of R130 I said is fine.This month Vodacom debited me double the amount when I call and check why they say am on a new contract of 700mb & 50minutes for R256 which I haven’t authorised.And like seriously who will sign up for 700mb at R256🤦🏽♀️.I never authorised this contract they just went ahead and put it on my package without talking to me when I request now for it to be cancelled they telling me is 24months contract I can’t cancel it .This is ***** by Vodacom because I never agreed to this contact they sign me on