Sometimes it seems like Notion content updates take a long time to sync to Super. But understanding how the caching works helps.
Notion caches page updates
Changes from Notion are cached by them before they come to Super, and sometimes there can be a 5-second gap between updates from Notion.
If you are still editing a block in Notion, then it will take longer for those changes to be published by Notion for Super to access.
So the trick is, click outside of the block you are editing, and wait for 5 seconds for Notion to save and publish the changes on its servers
Super caches page updates
Usually, changes in the dashboard preview take a few minutes to be published to your site, but sometimes this can take a few minutes but should happen automatically. Plus, different browsers are more aggressive at reading from the cache. You can try using a private/incognito session and clearing your browser cache to help speed things along.