Failed to cancel my Internet service

I have submitted a cancellation form to cancel my internet/DSL service in December. I have included all the required documents for this service to be cancelled. After I received my invoice end of January I saw the internet service was still active. I have phoned customer services again and they told me they I must forward it to TOC escallations which I did. Same thing end of February, I have forwarded it again to escallations. Up to now my account keep on adding up and since December and I am getting no feedback. I haven't even touched my Telkom internet service since December.