Unable to Generate an Embed for this URL

Hello,

I continue to get this warning when trying to embed links with the multimedia tool. I've tried several different website links and continue to get the same error.  I use this feature all the time and have never had this problem.  Please assist.

"We are unable to generate an embed for this URL. Please check that the URL is valid and the content is publicly accessible."

Here are a few of the links that are not embedding:

1. https://www.combathumantrafficking.org/about-human-trafficking
2. https://www.forensicnurses.org/page/aboutSANE
3. https://www.safeta.org/page/HumanTrafficking