Embedded vimeo or youtube video needs to play directly in full screen mode by clicking a custom play button

I have a requirement to play YouTube or Vimeo embedded video in fullscreen mode directly using the players' API by clicking the custom play button.

I tried this codepen method: https://codepen.io/fregante/pen/GgOvLM

But I can't able to exit the fullscreen mode by clicking the player exit fullscreen button, in youtube its says fullscreen not available

I am stuck, help me!!!

   var requestFullScreen = iframe.requestFullScreen || iframe.mozRequestFullScreen || iframe.webkitRequestFullScreen;  if (requestFullScreen) {    requestFullScreen.bind(iframe)();  }}