Cars transmission feels like its slipping in and out of gear.but sometimes wont move

Me re likely a problem within the fly by wire throttle body - accelerator pedal system .. Highly recommend visiting local auto repair facility for diagnosis .. There is nothing for the DIYer to attempt.

If you are able to come to a stop that indicates you eventually can move the car, correct? How do you get the car up to speed after you have no pedal power? Do you turn the car off and restart it and it works fine? Or do you have to give it much more throttle to get going? Alex