Do you currently have the embed removed from the page: https://www.clavefineart.com/en/claudine-drai-claude-de-soria-dames-2/ ? (i believe this is the correct page)
Screen Shot 2021-10-12 at 12.52.32 PM.png
I can force insert it with developer tools, but this does not give the same idea.
Screen Shot 2021-10-12 at 12.56.43 PM.pngPlease note with the Mobile layout: Your embed has width and height built in. width="640px" height="480px" so it will want to maintain these dimensions even for mobile layouts (this is why it pushes off the page).