FOX - WooCommerce Currency Switcher Professional

Plugin URL: https://yithemes.com/themes/plugins/yith-woocommerce-product-bundles/

• to your current child wp theme file functions.php add next code:

  add_filter('woocs_fixed_raw_woocommerce_price', function ($tmp_val, $product, $price) {
      if (!$price) {
          $tmp_val = $price;
      }
  
      return $tmp_val;
  }, 99, 3);