Vodacom contract cancellation

I called Customer Care early in January 2020 as my contract expired in September 2019 and i requested the contract to be cancelled. Vodacom however continued deducting the monthly subscription and eventually I stopped the debitorder at my bank. Then I got a SMS from Hammond Pole and Dixon attorneys as the account was in arrears. I explained the situation to them as well and after them also not getting feedback from Vodacom, they requested me to contact Vodacom direct... To no avail...... Please assist in cancelling my contract urgently. Kindly let me have your feedback in writing to ***. Thankyou Mrs AJ Warricker