Videoplayer code doesn't work

I wrote a code for start playing a video when a user click a customized button ( not the videoplayer button), the first time ( 2 weeks ago) the code work, but now, the same code doesn’t work.
The first video was recorded 1 week ago and the code work only in preview mode not in live site, the second video recorded more recently shows that the same code does not work neither in the preview nor in the live site.
WHY???

First video: https://www.screencast.com/t/vTemiXfggu
Second video: https://www.screencast.com/t/flmJXXrJx

This is the code

export function btnDoor_click(event) {
$w('#btnDoor').hide();
$w('#imgSopraVideo').hide();
$w('#videoGrosso').play();
}

See @givemeawhisky comment in this thread . The video size limit is most likely your problem.