Widget Youtube video using Gutenberg not showing in posts

Hi there,
On my client’s website, when I use the Youtube widget in Gutenberg editor for the posts, the video does not appear/show when reading the post without being connected.
I’ve been through the forum and tested all the proposed solutions but nothing works on my client’s website.

There are more than 30 posts, we do not want to change them one by one.

Can you help me

The page I need help with: [log in to see the link]