Hi @realestaterph
It sounds like the theme could be outputting an error. If a theme or plugin outputs an error on the page, it has the potential to break other plugins using JavaScript, in this case, Page Builder.
Here is how to open the browser console https://www.ads-software.com/support/article/using-your-browser-to-diagnose-javascript-errors/#step-3-diagnosis. Errors will be printed in red text. Temporarily deactivate all plugins including those authored by SiteOrigin. In that state with only your normal theme activated and no plugins, are there errors in the browser console when editing a page in WordPress? If so, please, take a screenshot, upload to imgur.com and send the link to theme support so they can take a look.
In addition to the above, you could perhaps try adding the following plugin https://www.ads-software.com/plugins/enable-jquery-migrate-helper/. As far as I’m aware, jQuery Migrate was removed in WordPress 5.5 causing many themes and plugins to produce errors.