Auth session killed after redirect | laravel 5.1

When I call:

Auth::loginUsingId($user->id, true);
print_r(Auth::user());

...It's ok. But when I have this function after that:

return redirect('/');

Now in mydomain.com I called print_r(Auth::user()); and it return null;

Here is my Kernel.php

class Kernel extends HttpKernel
{

    /**
     * The application's global HTTP middleware stack.
     *
     * @var array
     */
    protected $middleware = [
        \Illuminate\Foundation\Http\Middleware\CheckForMaintenanceMode::class,
        \App\Http\Middleware\EncryptCookies::class,
        \Illuminate\Cookie\Middleware\AddQueuedCookiesToResponse::class,
        \Illuminate\Session\Middleware\StartSession::class,
        \Illuminate\View\Middleware\ShareErrorsFromSession::class,
        \App\Http\Middleware\VerifyCsrfToken::class,
    ];

    /**
     * The application's route middleware.
     *
     * @var array
     */
    protected $routeMiddleware = [
        'auth'           => \App\Http\Middleware\Authenticate::class,
        'auth.basic'     => \Illuminate\Auth\Middleware\AuthenticateWithBasicAuth::class,
        'guest'          => \App\Http\Middleware\RedirectIfAuthenticated::class,
        'admin'          => \App\Http\Middleware\AdminMiddlware::class
    ];

}

Laravel version: Laravel Framework version 5.1.46 (LTS)

via Chebli Mohamed