Youtube embed suddenly stopped working

Hi. Today, suddenly, my Youtube embed stopped working. I had been using a plugin. I tried other plugins, and I tried the default option. All that is showing is either a blank space where the videos used to be, or a black box. Now on default, it’s a black box. I have the url on a separate line, etc. Obviously, I had this correct as it had been working fine. The videos were there earlier today, then suddenly they weren’t.

https://hardonhollywood.com/keepingviolet/what-is-violence-on-django-unchained/

Thanks for your help–I’m going on a month long trip in a week, and am worried I now have a major problem before I leave!! (not good)