Laravel/Passport - token response empty

I create an authentication with Passport and want use oAuth 2.0. I can create an authorization with /oauth/authorize?client_id=3&redirect_uri=http://local.docker:8080/auth/callback&response_type=code&scope=conacts. The next step is to get an access_token with the code.

So I create this route:

Route::get('/auth/callback', function (\Illuminate\Http\Request $request){
    $http = new \GuzzleHttp\Client();
    $response = $http->post('http://nginx/oauth/token', [
        'form_params' => [
            'grant_type' => 'authorization_code',
            'client_id' => '3',
            'client_secret' => 'dEVfXQaelMazZgHx15C1K6ZtretIwRU6jLBNwOB4',
            'redirect_uri' => 'http://tea.local.docker:8080/auth/callback',
            'code' => $request->get('code')
        ],
    ]);

    $body = (string) $response->getBody();

    echo '<pre>', print_r(json_decode($body, true));
});

In the $body should be a json-object, but the response is empty.

In log-file I found following lines:

[2019-03-28 11:40:15] laravel.ERROR: Argument 1 passed to Illuminate\Cookie\Middleware\EncryptCookies::encrypt() must be an instance of Symfony\Component\HttpFoundation\Response, null given, called in /var/www/html/www/vendor/laravel/framework/src/Illuminate/Cookie/Middleware/EncryptCookies.php on line 68 {"userId":966,"exception":"[object] (Symfony\\Component\\Debug\\Exception\\FatalThrowableError(code: 0): Argument 1 passed to Illuminate\\Cookie\\Middleware\\EncryptCookies::encrypt() must be an instance of Symfony\\Component\\HttpFoundation\\Response, null given, called in /var/www/html/www/vendor/laravel/framework/src/Illuminate/Cookie/Middleware/EncryptCookies.php on line 68 at /var/www/html/www/vendor/laravel/framework/src/Illuminate/Cookie/Middleware/EncryptCookies.php:133)
[stacktrace]
#0 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Cookie/Middleware/EncryptCookies.php(68): Illuminate\\Cookie\\Middleware\\EncryptCookies->encrypt(NULL)
#1 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(163): Illuminate\\Cookie\\Middleware\\EncryptCookies->handle(Object(Illuminate\\Http\\Request), Object(Closure))
#2 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Illuminate\\Http\\Request))
#3 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(104): Illuminate\\Routing\\Pipeline->Illuminate\\Routing\\{closure}(Object(Illuminate\\Http\\Request))
#4 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Router.php(682): Illuminate\\Pipeline\\Pipeline->then(Object(Closure))
#5 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Router.php(657): Illuminate\\Routing\\Router->runRouteWithinStack(Object(Illuminate\\Routing\\Route), Object(Illuminate\\Http\\Request))
#6 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Router.php(623): Illuminate\\Routing\\Router->runRoute(Object(Illuminate\\Http\\Request), Object(Illuminate\\Routing\\Route))
#7 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Router.php(612): Illuminate\\Routing\\Router->dispatchToRoute(Object(Illuminate\\Http\\Request))
#8 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(176): Illuminate\\Routing\\Router->dispatch(Object(Illuminate\\Http\\Request))
#9 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(30): Illuminate\\Foundation\\Http\\Kernel->Illuminate\\Foundation\\Http\\{closure}(Object(Illuminate\\Http\\Request))
#10 /var/www/html/www/vendor/spatie/laravel-cors/src/Cors.php(28): Illuminate\\Routing\\Pipeline->Illuminate\\Routing\\{closure}(Object(Illuminate\\Http\\Request))
#11 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(163): Spatie\\Cors\\Cors->handle(Object(Illuminate\\Http\\Request), Object(Closure))
#12 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Illuminate\\Http\\Request))
#13 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/TransformsRequest.php(21): Illuminate\\Routing\\Pipeline->Illuminate\\Routing\\{closure}(Object(Illuminate\\Http\\Request))
#14 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(163): Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest->handle(Object(Illuminate\\Http\\Request), Object(Closure))
#15 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Illuminate\\Http\\Request))
#16 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/TransformsRequest.php(21): Illuminate\\Routing\\Pipeline->Illuminate\\Routing\\{closure}(Object(Illuminate\\Http\\Request))
#17 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(163): Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest->handle(Object(Illuminate\\Http\\Request), Object(Closure))
#18 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Illuminate\\Http\\Request))
#19 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/ValidatePostSize.php(27): Illuminate\\Routing\\Pipeline->Illuminate\\Routing\\{closure}(Object(Illuminate\\Http\\Request))
#20 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(163): Illuminate\\Foundation\\Http\\Middleware\\ValidatePostSize->handle(Object(Illuminate\\Http\\Request), Object(Closure))
#21 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Illuminate\\Http\\Request))
#22 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/CheckForMaintenanceMode.php(62): Illuminate\\Routing\\Pipeline->Illuminate\\Routing\\{closure}(Object(Illuminate\\Http\\Request))
#23 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(163): Illuminate\\Foundation\\Http\\Middleware\\CheckForMaintenanceMode->handle(Object(Illuminate\\Http\\Request), Object(Closure))
#24 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Routing/Pipeline.php(53): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}(Object(Illuminate\\Http\\Request))
#25 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(104): Illuminate\\Routing\\Pipeline->Illuminate\\Routing\\{closure}(Object(Illuminate\\Http\\Request))
#26 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(151): Illuminate\\Pipeline\\Pipeline->then(Object(Closure))
#27 /var/www/html/www/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(116): Illuminate\\Foundation\\Http\\Kernel->sendRequestThroughRouter(Object(Illuminate\\Http\\Request))
#28 /var/www/html/www/public/index.php(53): Illuminate\\Foundation\\Http\\Kernel->handle(Object(Illuminate\\Http\\Request))
#29 {main}

via Chebli Mohamed