Injustice in the face of theft: Old Mutual Insure's Unfair Denial of Coverage

My car experienced a mechanical failure and we were uncertain about the cause. After an investigation, it was found that a part had been ******, leading to the mechanical issues. We filed a theft claim with Old Mutual, but they rejected it on the grounds of mechanical failure and overlooked the theft aspect entirely. It feels unjust and frustrating that I have insurance coverage for theft, yet they are refusing to address it due to an unrelated issue. Their actions are unacceptable, and I would not recommend them as an insurance provider to anyone.