Warning: Undefined array key "id" in /var/www/html/shopshop/src/Controller/CartController.php on line 29

Fatal error: Uncaught TypeError: MyApp\Model\CartModel::getOneCart(): Argument #1 ($id) must be of type int, null given, called in /var/www/html/shopshop/src/Controller/CartController.php on line 30 and defined in /var/www/html/shopshop/src/Model/CartModel.php:27 Stack trace: #0 /var/www/html/shopshop/src/Controller/CartController.php(30): MyApp\Model\CartModel->getOneCart() #1 [internal function]: MyApp\Controller\CartController->cart() #2 /var/www/html/shopshop/src/Routing/Router.php(97): call_user_func() #3 /var/www/html/shopshop/public/index.php(26): MyApp\Routing\Router->route() #4 {main} thrown in /var/www/html/shopshop/src/Model/CartModel.php on line 27