Hi there!
Thanks for reaching out.
Could you please let us know which versions of Joomla and SP Page Builder you're currently using?
Also, if possible, please share a short screen recording demonstrating the issue. It would be helpful to see the steps you follow when removing the Joomla article content, editing the page with SP Page Builder, saving it, and then observing the original article content reappear.
If I understand it right, this behavior is not expected, so we'd like to investigate it further.
Best regards,