Your changes are not showing up
Caching, processing and staging.
New knowledge needs processing
Added material is not usable instantly. Large files take longer. Wait a few minutes, then check in Test Arena rather than on your live site.
You are seeing a cached page
Check in a private window. Course platforms in particular cache aggressively, and their admin previews often do not reflect published changes.
You edited a different clone
Easy to do with several clones, especially if they share a name. Check the clone name at the top of the editor against the data-clone value in your embed code.
Your site was never republished
Most site builders keep edits in a draft until you publish. Publish and check again.