Car Accelerates On Its Own problems of the 2018 Hyundai Tucson

Once my brand new Tucson hit 500 miles on it, it suddenly unintentionally accelerates while my foot is already pressing firmly on the break pedal. The first time, it happened as I was approaching the peak of a hill. I was going 25 mph. My foot was already pressing on the breaks, anticipating the decline, when my car jolted forward and took off. My foot slammed on the breaks even harder, however I watched my speedometer hit 40 mph while simaltaneously, my rpm decreased to 1. . . (yes, down a hill. ) for about 5-7 seconds the rpm and seppdometer would not increase or decrease once hitting 40 mph and 1 rpm. I had to lean over the wheel and slam my breaks to the floor before I regained control of the vehicle. Once this occurred, the car lagged, struggling to accelerate throughout the remainder of the drive (all flat roads). It is now day 5 of experiencing this, and it now occurs multiple times every time the vehicle is in motion, whether breaks are being applied prior, or not, regardless of the type of road I am on (flat, hill etc. ) I was exiting a parking garage that had a mediocre ramp to exit the garage. My vehicle was going 12 mph when I turned right to proceed down the ramp. My foot slowly pressed the break pedal, and my vehicle accelerated to 28 mph, and maintained that speed for 3 seconds, before responding to my breaks. Yes, my foot had the breaks pressed all the way down. Another example, yesterday I was on a flat road driving at 27 mph when it suddenly accelerated to 45 mph, and the rpm dropping suddenly from 2, to 1. After a few seconds of my foot slammed on the breaks I regained control and pulled the car over. I turned the engine off and waited about 5 minutes. When I turned it back on, and began driving (3 minutes left in my drive), the car continued to lag, lunge forward, and could not reach speeds higher than 30 mph. This car is brand new.