The contact owns a 2021 Mazda CX-5. The contact stated that while at a complete stop, the vehicle was rear-ended by another vehicle driving approximately 40 - 50 MPH. The contact stated that due to the crash, the driver's seat unexpectedly reclined, and the driver's head restraint detached and landed in the car seat in the rear seat. The contact also stated that the air bags failed to deploy during the crash. A Police report was filed. The contact was transported to a local emergency room and was treated for a fractured right fibula and whiplash. The vehicle was towed to a service center for an insurance claim and inspection. The contact was concerned that the air bags did not deploy and stated that the failure could have resulted in more catastrophic injuries. The failure mileage was approximately 50,000.