There may be several reasons why your changes are not visible online:
The website hasn’t been updated properly
If the changes aren't saved and updated within the website builder, they won’t be visible online. After making any changes within the editor, click the Update website button in the top right corner:
You're having browser/network/DNS cache issues
Try clearing the cached files, and restarting your internet router and/or device.
You may also try accessing your website using:
Incognito (private) internet browser window
Another network: Wi-Fi vs mobile data
Another device: laptop, tablet, mobile
You've been editing the website using multiple browser tabs/devices simultaneously
If the website builder is open in several browser tabs or devices simultaneously, the changes you make may not be saved properly, thus the content may not be updated properly, either.
Make sure that you have a single editor tab open, update your website again, and check if the changes reflect online.