You may find you have inconsistent page restrictions across your Confluence. This may be more of a common issue as your Confluence instances grow larger.
By following this guide, you will be able to fix these inconsistencies.
“a page that has different page restrictions that those you have set with the Auto-Restrict feature in either the Space/System settings”.
Please use this feature with caution as this will force pages to have the exact same restrictions as those you've defined in Auto-Restrict. This means any manually added users/groups you've added directly to the page that you have not defined in Auto-Restrict will be removed.