Show number of failed orders

gistfile1.txt

add_action( 'woocommerce_admin_order_data_after_order_details', 'failed_orders_evd', 10, 2 );
function failed_orders_evd( $order ) {

    $customer_orders = get_posts( array(
        'numberposts' => -1,
        // 'meta_key'    => '_customer_user',
        'meta_value'  => $order->get_billing_email(),
        'post_type'   => 'shop_order',
        'post_status' => array('wc-failed'),
    ) );

    $orders_count = '<strong style="color:red">' . count($customer_orders) . '</strong>';

    echo'<p>' . __( 'Failed orders: ' ) . $orders_count . '</p>';

}