Embedded videos from youtube are not showing up in iPhones in both Chrome and Safari browsers, in the Spiel theme. What can be causing this and what can I do about it?

You can see in this post: https://mustbringsnacks.com/2024/04/30/a-day-in-canyonlands-national-park/

About 3/4 down the page, there are three embedded youtube videos that are just showing a blank white spaces in iPhones. Thanks for you help