VODACOM insurance don't want to pay

My mother has 3 vodacom numbers with 3 phones under contracts, 1 iphone6 plus and 2 iphone6, when she travels she puts the device that she takes on insurance with vodacom. End of 2014 she traveled, she insured the iphone6 that she took before leaving SA, and cancelled the insurance when she came back to SA without losing the device. Apr 2015, she signed the contract for her 2nd iphone6, and insured the 6plus because she thinks 6plus is the most expensive. She put the sim from 6plus into the new 6, and used the new sim in the 6plus, and took the 6plus on her trip to China in May and June, the 6plus was lost in China in June. Now when we try to claim from the insurance, we are told to contact Cellsure who we did not know existed, and after over 10 calls, they reject the claim because the insured sim and device were separated. The vodacom person in Eastgate vodashop who helped us signed the 2nd iphone6 and the insurance for 6plus did not inform us such terms at all. This is like rejecting a household insurance claim because the furniture changed, we insured a device a property, not the relationship between a sim and phone. Please someone help! Would customer protection act help?