Declined claim by Vodacom, while paying for the service.

I got a deal for two phones, then I decided to insure both of them, now when I'm supposed to claim they telling me that I only insured one. After telling them million times when I claim I wont have problems, they said Yes. Now they telling me that the other sim is not insured. Please sort the matter out, I pay way too much on my contract for such service.