我添加了以下内容，以创建基于重量的附加费的额外购物车费用，但税不适用于额外费用-我遗漏了什么？
问题站点为http://oldhousestore.co.uk/

代码已创建

add_action( 'woocommerce_cart_calculate_fees', 'shipping_weight_fee', 30, 1 );
function shipping_weight_fee( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    // Convert cart weight in grams
    $cart_weight = $cart->get_cart_contents_weight() * 1000;
    $fee = 0.00697; // Starting Fee below 1000g

    // Above
    if( $cart_weight > 1000 ){
        for( $i = 1000; $i < $cart_weight; $i += 1000 ){
            $fee +=0.00697;
        }
    }
    // Setting the calculated fee based on weight
    $cart->add_fee( __( 'Energy Surcharge' ), $fee, false );

    // Convert cart weight in grams
    $cart_weight = $cart->get_cart_contents_weight() * 1000;
    $fee = 0.00165; // Starting Fee below 1000g

    // Above
    if( $cart_weight > 1000 ){
        for( $i = 1000; $i < $cart_weight; $i += 1000 ){
            $fee +=0.00165;
        }
    }
    // Setting the calculated fee based on weight
    $cart->add_fee( __( 'Environmental Surcharge' ), $fee, false );
}

**预期：**总税额包括附加费、购物车项目和运费
**观察结果：**总税额仅包括购物车商品和运费