The contact owns a 2018 Jeep Grand Cherokee. The contact stated that while driving 35 MPH, the check engine warning light illuminated after the Auto/Start unavailable message was displayed and became inoperable. Upon starting the vehicle, the Auto START/STOP unavailable message was displayed. The contact received notification of NHTSA Campaign Number: 24V838000 (Service Brakes, Hydraulic); however, the part to do the recall repair was not yet available. The vehicle was towed to the local dealer, where it was diagnosed that the camshaft kit needed to be replaced. The dealer informed the contact that the part was on backorder. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The manufacturer opened a case and attempted to expedite the parts. The failure mileage was approximately 71,500. VIN tool confirms parts not available.