payout on hijacked and not recovered vehicle

Good day

I was hijacked driving my fathers vehicle, the insurance was in my fathers name and everything, now miway insurance doesn't want to payout when the vehicle was never recovered. Even though on the contract sent to my father it clearly states that if someone was driving the vehicle other then the owner, and it was hijacked or written off, then the owner will be entitled to pay an extra amount of money (R5000 or so) additional excess.

I really need assistance on this matter.

Regards Itumeleng