Multiple classes behind one facade

Facade

namespace App\Webshop\Facades;

use Illuminate\Support\Facades\Facade;

class Webshop extends Facade
{
    /**
     * @return string
     */
    protected static function getFacadeAccessor()
    {
        return \App\Webshop\Webshop::class;
    }
}

ServiceProvider

namespace App\Webshop;

use Illuminate\Support\ServiceProvider;

class WebshopServiceProvider extends ServiceProvider
{
    /**
     * @return void
     */
    public function register()
    {
        $this->app->bind(\App\Webshop\Webshop::class, function() {
            return new Webshop(new Cart(), new Checkout());
        });
    }
}

Webshop

namespace App\Webshop;

class Webshop
{
    /**
     * @var Cart $cart
     */
    private $cart;

    /**
     * @var Checkout $checkout
     */
    private $checkout;

    public function __construct(Cart $cart, Checkout $checkout)
    {
        $this->cart = $cart;
        $this->checkout = $checkout;
    }

    /**
     * @return Cart
     */
    public function cart()
    {
        return $this->cart;
    }

    /**
     * @return Checkout
     */
    public function checkout()
    {
        return $this->checkout;
    }
}

When i run:

Route::get('test1', function () {
    Webshop::cart()->add(1); // Product id
    Webshop::cart()->add(2); // Product id

    dd(Webshop::cart()->totalPrice());
});

It dumps "24.98" (a price calculation)

But when i run:

Route::get('test2', function () {
    dd(Webshop::cart()->totalPrice());
}); 

It shows me "0"

I think the problem is in the ServiceProvider, because when it registers it creates new objects of Cart and Checkout

How can i fix this issue?

via Yooouuri