Cancellation don't get actioned

I have been trying now for over a year to CANCEL my data contract. I just don't have the need for it. I've done the paperwork, I've chatted to a person at Telkom. They tell me it will be cancelled, and 20 months later, the contact is still going! I'm sick of it, I WANT TO CANCEL!!!!!!!! I'm paying for data I dent use, and just not able to cancel this. Enough, worst company on the planet. My cancellation ref ***1. I received and sms to say they will action, but NO, i got another bill this month and even with a debit order, all of a sudden i'm behind! NO NO NO, Telkom, you are disgusting!