I can’t update any page created with Siteorigin Builder

I Installed yesterday Siteorigin theme and plugins:

SiteOrigin Corp

Page Builder by SiteOrigin
SiteOrigin CSS
SiteOrigin Widgets Bundle

I’re just begining with my first page since yesterday and everything were fine; but today when I tried to continue, saving the new version of my first page, pressing the Update button, WordPress bring up this page https://monterreynegocios.com/wp-admin/post.php
It only says:
Oh! That page could not be found.
Try the search form below or browse using the main menu above.

I already clear cache several times, and installed a plugin to manage cache, but the problem continue, I can’t do nothing.

With my original theme “Twenty Twenty-Four” this error never occured, so, is there anything wrong with this tools?

Am I doing somthing wrong?

Does somebody may help me???