Count products with custom metadata field in an order

{
    $userid="";
    $integration_status="";
      // Get an instance of the WC_Order object
        $order = wc_get_order( $order_id );
        $email  = $order->get_billing_email();
        $name = $order->get_billing_first_name();
        $items = $order->get_items();

        $devicecount =0;        

        foreach ( $items as $item ) {
            $product_name = $item->get_name();
            $product_id = $item->get_product_id();
            $product_variation_id = $item->get_variation_id();

            $productToBeIntegrated=get_post_meta($product_id,'_wootraccar_integration', true);
            //$integration_status.=$productToBeIntegrated;

            if ($productToBeIntegrated=="yes") {
                $devicecount = $devicecount +  $item->get_quantity();
                $integration_status.=$devicecount;          }
        }