User Deprecated: Since symfony/framework-bundle 5.1: Using type "Symfony\Component\Routing\RouteCollectionBuilder" for argument 1 of method "App\Kernel:configureRoutes()" is deprecated, You need to update Kernel class to start using RoutingConfigurator instead of RouteCollectionBuilder. You can do it automatically by updating the recipe (composer recipes:install symfony/framework-bundle --force)