Log in to the admin panel and try to delete records. You should get a blank page. Next, remove or hide the delete button from the template. The path of the template is web/staff/tpl.(table-name).search.inc.php.

Yes, but only on how to remove the non-administrator profile?

Hi, in the templates ( any files that starts with "tpl." ), you can use IsAdmin function to hide things from non-Admin users like

<?php if ( $sys->IsAdmin() ) { ?>

...anything here will not be shown to non-admin users...

<?php } ?>