TL* THE CONTACT RENTED A 2019 DODGE GRAND CARAVAN. THE CONTACT WAS SEATED IN THE REAR OF THE VEHICLE BEHIND THE DRIVER'S SEAT. WHILE ATTEMPTING TO ADJUST THE SEAT, THE HEADREST STRUCK THE BACK OF THE CONTACT'S NECK. THE CONTACT STATED THAT SHE WAS EXPERIENCING HEADACHES DUE TO THE INJURY. MEDICAL ATTENTION WAS NOT RECEIVED. THE CONTACT INFORMED AVIS CAR RENTAL SAN FRANCISCO INTERNATIONAL AIRPORT (780 N MCDONNELL RD, SAN FRANCISCO, CA 94128, (650) 877-6780) OF THE FAILURE. THE MANUFACTURER WAS NOT NOTIFIED OF THE FAILURE. THE CAUSE OF THE FAILURE WAS NOT DETERMINED. THE VIN WAS UNKNOWN. THE FAILURE MILEAGE WAS 11.