Your seat switch has been knocked out of adjustment (Bump) or has failed (Bump) or has become unplugged (Bump).
The reason it only runs when the brake is on is because the safety interlock wiring permits the engine to run with the seat unoccupied ONLY WHEN THE BRAKE IS ON.
Because of a problem with your seat switch, it thinks the seat is empty, so it kills the engine when you let up the brake pedal.

yes thats it,just disconnected two wires under seat runs just fine now,have to order a new part tks for your help its appricated,