Volkswagen Golf 2014: Acceleration problem

We haven't had specific reports of this problem, but it does sound like a serious one that needs fixing urgently. It can be hard to determine the cause of a problem if it doesn't happen while the dealer has the car, but I would suggest you take it back to the dealer and ask them to check it again. I have heard of one car that had a problem with the throttle pedal position sensor, which on the surface sounds like a likely candidate for you problem.