Unacceptable - Poor Maintenance

My grandmother and grandfather has been with OUTSURANCE for years. They stay in Pretoria and had a huge storm with with strong winds. Their thatched roof was lifted by the wind and came crashing down on their tiled Lapa where the sit every morning and afternoon to drink their coffee. The Lapa is open and well maintained by my grandparents that are in their late 80's. They send through the claim and were informed that the claim was denied due to poor maintenance. There was nothing wrong with the thatched roof. They pay their installment and seldomly claim. This is unacceptable, why do they have insurance then if it does not cover a strong wind damaging their property????????????????????????????