Button Sound Plays Only on First Click

Unity Engine
1

Hello, i am desperate to find solution. Here is my code on button. When i first time click button, sound !!!SOMETIMES!!! works, after that u can click that button all day long , it doesnt play any sounds… Whats wrong here? Pls help…

public void OnMouseDown()
    {
       if(GetComponent<AudioSource>().isPlaying)
        {
            GetComponent<AudioSource>().Stop();
            GetComponent<AudioSource>().PlayOneShot(sound);     
        }
         else
        {
            GetComponent<AudioSource>().PlayOneShot(sound);
        }
2

Why can’t you just call Play() instead of Stop() and PlayOneShote()?