Putting Youtube Video In Posts Template

Hi all, I’m trying to put a video in the posts template that auto-populates a different video each time. I have the custom field set up but the design of the posts template is causing me trouble.

When I input the video element on the posts page and put the url in the normal place, everything goes fine. But when I try to ‘Get Video From Posts’, the video element disappears.

Any help is greatly appreciated. Thank you

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