Possible ***** - adding contract insurance cover without a request from customer

On 12 January 2019 I upgraded my data contract at the Vodacom Shop in Greenstone. When the contract was printed out it included "Contract Cover Insurance" for R6.99. I had not requested this and it was not on my previous contract. The person who assisted me said that he couldn't do anything as it was a Saturday. He told me not to sign that line in the contract and that I needed to contact Cell-Sure on Monday to ask them to cancel it. I battled to get through to Cell Sure on the phone so I sent them an email. ********** responded: "This R6.99 is not one of our products. Please refer to the consultant in store to canel." I went back to the Vodacom store in Greenstone and asked them to cancel the insurance. They claimed that they had cancelled it but could not show me the revised contract. On 31 January I received an SMS from Vodacom to say that contract cover insurance had been activated on my account and that I should phone 082 135 to cancel it if not required. I phone the 082135 number and went through the process of identifying myself only to be told that they couldn't assist and that I needed to contact Cell Sure on ********** to cancel. I tried to call Cell Sure all day on 31 January and the number was permanently engaged. Today (1 Feb) I called ********** and the welcome message identified that I had got through to Vodacom insurance and it was administered by Finrite. Cell Sure was out of the picture. As soon as I selected 2, the call dropped. I continued to try and could never get through to an agent. I phoned 082135 again only to be told that they could not assist and they had to transfer me to Vodacom Insurance. They tried and the call immediately dropped. My questions: 1 Did the Vodacom Shop purposely add the contract cover knowing that it was very difficult to cancel it. It is not a significant amount but would add up if added to all contracts. 2 My contract is with Vodacom, not an Insurance Company. Vodacom bill me and they claim that they are unable to cancel this cover. Is this legal?