On Windows PC, how to use Java's Robot to close an On_Screen Keyboard window?

Question

My Java app needs to open an On-Screen-Keyboard app [ osk.exe ], then use Java Robot to move the mouse to the close button position and press the mouse to close the app, but it won't close, yet when I clicked on my mouse, it does close the app, why ? How to use Java Robot to close it ?

Here is my sample code :

  try
  {
    Runtime.getRuntime().exec("cmd.exe /c osk.exe");
    Robot robot=new Robot();
    robot.delay(100);           // Delay to let the application load
    robot.mouseMove(1750,880);  // Move to On_Screen Keyboard's [ osk.exe ] upper right corner where the close button [ X ] is.
    robot.mousePress(InputEvent.BUTTON1_MASK);
    robot.mouseRelease(InputEvent.BUTTON1_MASK);
  }
  catch (Exception e) { e.printStackTrace(); }