Car Accelerates On Its Own problems of the 2015 Nissan Altima

While parallel parking on the street next to my home, my car experienced a sudden acceleration. I had pulled into the space between the two vehicles in the photo provided. While my foot was on the brake, and the car stationary, I placed the gear selector into reverse in order to back away from the car in front. As I started to release the brake, my car unexpectedly accelerated. I pressed against the brake. With the wheels skidding along the asphalt and having the front wheels turned slightly, the car hit the curb and the car behind me. All cars pictured are family members cars. I have contacted the Nissan complaint hot line. They informed me that there is a update for the control unit, but that what I had experienced is not a condition for the update.