Contract Still Not Cancelled

I have Polite-fully requested a cancellation for one of our Mobile Data lines with the following number *** the original email was sent on the 3rd of November so it can be cancelled and converted to a prepaid on the the 30th of November 2015. I ended up sending the same email 3 times on different occasions since i was not getting a response from Telkom Mobile. Before month end of November I called the call Centre to find out if cancellation was loaded as requested and to my amazement no cancellation was loaded since the agent I spoke to said he was not seeing any email sent. And now this month I'm being billed a ridiculous amount. Here are the Ref Numbers I have been given SM177784 and ***0. So far I still havent got any response and if i dont receive any call within the next 24 hours telling me the requested number to be cancelled as the contract is finished, I will simply walk in to Telkom Store and there is goin to be hell to pay. My number is ***