Refusing to Cancel Line

I'm still waiting for my line to be cancelled. I cancelled it on the 3 July 2018 and they're still billing me. I did the online cancellation and received an email to say it's been cancelled, but they're still billing me. It's getting scary getting all these bills for a service I'm not even using. I've been using Web Africa and Vumatel since beginning July as they're much more reliable and don't take weeks to fix something.

Why do they think they're encouraging repeat customers by making it so hard to cancel their services? Who is going to want to sign up with Telkom in the future? They seem desperate for business as they keep on cold calling for contracts, so you'd think they'd work on their customer service side a bit. The agent who was looking into my problem was sweet and helpful, so I don't want to diss her, but I sure wish the company would get its act together.