Cancellation of contract

I was misinformed by a sales person from telkom mobile who sold me a contract in December 2016. I tried cancelling this contract from JANUARY 2017 right up to November 2017. I made hundreds of calls to them to sort this problem out. Every time I called they promised to escalate the matter and send someone to collect the mobile device and sim cards. I filled in cancellation forms five times and sent them by mail and submitted some via Telkom shops. They are deducting the monthly subscription by debit order although I have not used their services from January 2017.