The Jetta TDI has been modified by the dealer to conform to required tailpipe emission. When left in the driveway for approx. a week the engine turns over but shuts down immediately. Dealer says that the car must be locked to stop the battery from get drained???
I guess this is not really a 2021 Jetta . How old is the battery because I don’t think that locking or not locking would make that much difference . Of course if it is parked in your driveway it should be locked .
You can always try another dealer if there is one or an independent shop if you are out of warranty.
Since the battery has enough power to start the engine I doubt it is a battery problem.
Why the dealership claimed this is a mystery to me.
Can you provide more information?