I have a 2011 Jaguar XF with 33,000 miles on it runs flawless. Parked in mall, parked car, came out two hours later and turned it on.. shifter came up as usual but would not come out of park. Brake lights come on so they and sensor should be working properly. Had to get tow to Jaguar dealership. There was no message on console other than ignition on. Dealership claimed to run diagnostic test and it came back saying transmission fault. What does transmission fault indicate? There’s no way the tranny could have failed at this point.is the shifter faulty?

any suggestions helpful so I can talk knowledgeably to dealership.

thanks