Contract Cancellations Failure

I have a telkom freeme 1gb month to month contract, which I went into a telkom store to cancel and make pay as you go, end of November, 2017. According to their contracts, I must give 20 days notice, it is now over a month later, no one has contacted me, the contract is still active, and they are going to charge me for another months usage.. I know I am not the first person with this issue. It also seems they havent got a clue how their systems work, because today i went back in to the same store to find out what is going on, they say it has been sorted, but when I phone the helpdesk afterwards, they say the contract is still active. Great service, now i am happy with my decision to want to leave Telkom.