Unable to cancel contract

On 27th June 2017 we cancelled our month to month mobile contract with Telkom.I ported my number to MTN. I have a copy of the contract which clearly states "month to month" but the Telkom staff member loaded it as "24 month"contract. Telkom allocated a new number to my " account" and our account has been debited every month since then. I have emailed them with all details 3 times and been into the Telkom office at Blue Route but have been "unable to raise the dead".