I have got my volkswagen jetta steering wheel locked while parking down hill. Its feels like jammed. also the ignition not working, unable to move key and the gears are locked.

sounds like the parking pin is pinched by the weight of the vehicle , you have to kinda rock in the seat back and forth to get the shift freed up

this is why they install parking brakes on cars never let your car sit on the transmission while its in park as it is a very minor parking option which can allow the car to break loose and go where ever it wants to if you have to park on a hill never ever forget to apply that hand brake. it is a safety feature that will save your car and any one else from injury's. you are going to have to rock the car or get the car pushed back up the hill to release the gear now due to the weight of the vehicle (2 tons or more) that is now siting on a 2 inch pin that holds the park positon ..