How to remove 302 redirect from 404 error?

Question

Joomla

Hello! Right now the HTTP status code is 302, need 404.
Here is the full content of the error.php used:
/**
* @package Joomla.Site
* @subpackage Template.system
*
* @copyright Copyright (C) 2005 - 2016 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/
defined('_JEXEC') or die;
if (!isset($this->error))
{
$this->error = JError::raiseWarning(404, JText::_('JERROR_ALERTNOAUTHOR'));
$this->debug = false;
}
// Get language and direction
$doc = JFactory::getDocument();
$app = JFactory::getApplication();
$this->language = $doc->language;
$this->direction = $doc->direction;
?>
<?php
if ($this->_error->get('code') == '404') {
header("HTTP/1.0 404 Not Found");
header('Location: index.php?option=com_content&view=article&id=710');
exit;} ?>
On other sites I use this code and a 404 response.
<?php
// no direct access
defined( '_JEXEC' ) or die( 'Restricted access' );
?>
<?php
if ($this->error->getCode() == '404') {
echo file_get_contents(JURI::root().'/error-404');
}
?>
Tell me what is wrong and how to fix it? Thank you.