How Restrict access to admin dashboard by specific static ip?

i’m trying to restrict access to admin dashboard (wp-admin.php) by specific static ip so tried to add .htaccess to the wp-admin and set

<FilesMatch "admin\.php$">
Order deny,allow
Deny from all
Allow from 10.0.0.0/24
</FilesMatch>

but is not working and tried to install bulletproof plugin too and change the
<IfModule !mod_authz_core.c>
<IfModule mod_access_compat.c>
Order Allow,Deny
Deny from all
Allow from 000
</IfModule>
</IfModule>
</FilesMatch>

but not working to please any help and many thanks in advance.

By the time admin_init rolls around you should know if you’re doing AJAX or not. If you’re not, then check the IP. Keep in mind that anyone can fake that number.

add_action('admin_init', function() {

    if(defined('DOING_AJAX') && DOING_AJAX) {
        return; // ignore ajax
    };

    $ip = $_SERVER[ 'REMOTE_ADDR' ];

    if($ip !== '10.0.0.0') {
        wp_die(__('You are not allowed to access this part of the site'));
    }
});