2013 Hyundai Sonata drivetrain & axles problems

I pulled into a parking space and shut off the engine with my push button start, without putting the shifter into the park position. The vehicle allowed me to exit and the car started rolling backwards. I tried to re-enter the vehicle to engage the brake and was knocked onto the pavement by the driver door. I was forced between the bottom of the door and the pavement as the vehicle rolled past me and entered traffic, crossed to lanes and was stopped by a curb and a speed limit sign. Vehicle bumper was dented.

On monday september 22nd around 540pm on the 10 fwy going eastbound right before towne ave. As the traffic on the freeway began to slow I came to a complete stop. About 5 seconds after stopping I noticed that the car began to roll forward. I applied more pressure to the brake pedal however the car continued to slowly roll. I then stepped on the emergency break and the car did not stop. The car slowly rolled about 8 feet before it stopped on the back of a big rig trailer bumper.