I followed Shopify FB vid, works only in preview mode

Hey I’m very new to server side GTM. I just followed the whole video
Facebook conversion API for Shopify - YouTube , called " Facebook conversion API for Shopify"

When I’m in preview mode in the web container, it works. When I’m not in preview mode, nothing happens. This makes me think the website isn’t sending to GTM web container, or I don’t have something there to catch it. What do I need to do? Do I need to set up a “UA - base” kind of thing? I’m not sure if I need Universal Analytics or GA4, they’re both setup, I just need a little more foundational help to make what was in the video work while not in preview mode. Thanks!!