TELCOM DOES NOT ACCEPT TELEPHONE SERVICE CANCELLATION

I cancelled my Telcom account per email on 28 Feb 2018. I receive endless telephone calls for telkom agents , and the more I inform them that I cancelled the service Feb 2018, they persist in calling/calling and calling. At a stage I sent 6 emails from Postnet , as they never cancelled the website. Today they phoned me again , I explained to the caller they can stop calling. The lady informed me they would keep on phoning.