şunu bir deneyin,

add_action( 'wp_login_failed', 'pippin_login_fail' );
function pippin_login_fail( $username ) {
$referrer = $_SERVER['HTTP_REFERER'];
if ( !empty($referrer) && !strstr($referrer,'wp-login') && !strstr($referrer,'wp-admin') ) {
wp_redirect(home_url() . '/?login=failed' );
exit;
}
}

olmazsa bunu deneyin:

functions.php eklenecek:

if ( is_admin() && !current_user_can('manage_options') ) {
wp_redirect( get_bloginfo( 'url' ) );
}

eğer bu olmazsa bir de şunu deneyin:

add_action('init','custom_login');
function custom_login(){
global $pagenow;
$blogHomePage = get_bloginfo('url');
if( 'wp-login.php' == $pagenow && $_GET['action']!="logout" && $_GET['action']!="lostpassword") {
wp_redirect($blogHomePage);
exit();
}
}