Aug 14th, 9:49 pm - Vehicle was placed in park and driver got out. A few seconds later the vehicle started moving forward under its own power towards the driver who was now infront of vehicle walking foward away from vehicle. Passenger hopped over the driver seat to press on brake pedal to stop vehicle. At same time, driver turned around and noticed vehicle moving towards him. Passenger was able to stop vehicle but not before it ran off the driveway and into and over a recreational firepit area. Driver was on opposite side of this. Driver got in to vehicle, verified transmission was now fully engaged in Park, and reversed the vehicle off firepit area. Damage to both vehicle, and firepit ring and landscaping area. Security footage later confirmed vehicle was placed in park, brake lights went out, and vehicle remained stationary for approximately 3 to 5 seconds before driver exited vehicle. It was when driver shut door that vehicle then moved, as if the Parking pin did not engage or failed to stay engaged. Owner traded vehicle in with another dealer soon after, due to other ongoing issues involving the steering and brake system that had not been resolved. Approximately 11,580 miles on vehicle at the time of incident. No personal injuries reported.