PUT makes POST instead of updating value in Spring Boot

问题

I don't understand why, but whenever I do put operation in postman this method always creates new vehicle This is code for put mapping

@PutMapping("/{id}")
public Vehicle updateVehicle(@PathVariable long id, @RequestBody Vehicle vehicle){
    vehicle.setVehicleId(id);
    return vehicleRepository.saveAndFlush(vehicle);
}

This is code for post mapping

@PostMapping("")
public Vehicle newVehicle(@RequestBody Vehicle vehicle){
    return vehicleRepository.saveAndFlush(vehicle);
}

来源：https://stackoverflow.com/questions/61920671/put-makes-post-instead-of-updating-value-in-spring-boot