Why is the youtube vertical frame not displaying correctly?

Question

YouTube

Good afternoon! I am writing an application on cordova, I need to insert a broadcast (9:16) into the background. With a normal video (or a recording of the same broadcast), everything is fine, but black bars appear around the broadcast frame. Here is an example on a computer through the viewport: Most likely it's in youtube itself and the frame setting. url example

https://youtube.com/embed/ТРАНСЛЯЦИЯ?autoplay=1&showinfo=0&controls=0&rel=0&html5=1&w=720&h=1280&enablejsapi=1&widgetid=1