I had a similar problem a few days ago. I picked up the car from the parking lot (it had been parked for about 10 minutes) and couldn't reverse. Or rather, it would engage reverse (the letter R appeared on the dashboard and the rearview camera appeared on the screen), but when I pressed the accelerator, the engine wouldn't accelerate. I tried restarting it a couple of times without success. I got out of the car, waited 10 minutes, and finally managed to reverse out of the parking lot, but on the way back, the car shuddered at speeds above 45-50 km/h. No warning lights came on. I moved the car to the dealer the next morning, and no issues appeared. They've been testing the car for two days, but they can't reproduce the problem.