Carrier/rack problems of the 2008 Lexus IS

My 2008 Lexus Is250 passenger side windshield bracket clip break off, when I drive at a high speed I can hear the noise that the wind tapping against the windshield. Because the bracket clip Is broken, so it will not hold the windshield frame down. I affair that it will come off and hit someone behind or people on the side walk if someone happens to be jogging. When I look at it, it seem that the bracket Is poorly design. The car at this age should not happens if the design Is look carefully. I never see like this before, even my truck 300,000 mile the windshield bracket still strong.