Trying to cancel a contract.

Good day, I have been trying to cancel my contract which was signed on the 11 Oct 2017 and should have expired on the 31 Oct 2019. I have sent emails to the customer care line. I have called retentions and everyone keeps on insisting my contract expires in Feb 2020 as someone in their wisdom at Vodacom extended my contract and changed my package. They promise to sort out the issue and I never hear from the staff again. As from today I will be charging Vodacom for my time and administration costs at my current hourly rate.