If you get a 404 error when you're trying to edit a page or a saved row or module in Beaver Builder, usually the solution is to reset your permalinks.

To reset the permalinks for your site:

1. On the WordPress admin panel, go to Settings > Permalinks.

2. Click Save changes.
   If that doesn't solve the problem, continue with the following steps.

3. On the Settings > Permalinks page, make a note of your current permalink setting.
   If it's set to Custom structure, copy the text in the box so you can paste it back later.

4. Select Plain, then click Save changes.

5. Select the setting you had before.
   If you had Custom structure selected, paste the custom text into the text box.

6. Click Save changes.