CAR WAS IN MOTION, TURNING TO PARK ON SLOPE PARKING AREA THEN GEAR FALL OUT AND ROLLING BACKWARD, THEREFORE TRY TO SHIFT INTO PARKING GEAR, ALL GEARS DIDN'T WORK, GEAR SHIFT WAS NOT WORKING AT ALL THEN CAR ROLLED DOWNHILL TO OTHER SIDE OF CURVE. TO PREVENT ACCIDENT I GOT OUT TO STOP THE CAR FROM ROLLING BY HOLDING ON TO THE REAR DOOR HANDLE, COULD'NT STOP IT, IN THE PROCESS I HAD INJURY TO MY LEFT SHOULDER AND BACK.