Cell C Month to Month contract moved to 24 months without agreeing

I purchased 2 Month to Month contracts from Cell C on the 10th of January. The consultant said I can cancel any time, and the contract will come to an end after 30 days. When I tried to cancel both on the 25th of February, the consultant informed me that Cell C's terms and conditions have changed, and my contract was moved to a 24 month contract.

I never received any documentation informing me of the change, otherwise I would have cancelled. I never agreed to a 24 month contract, hence why I only took a month to month contract. I am also informed that all calls were recorded.

Can anyone please assist me in cancelling both my lines with Cell C?

I never agreed to a 24 month contract, and according to Consumer law, I cant be held liable.