Symfony FOS User Bundle registration form overriding error - symfony

Question

I am trying to override fos user bundle registration form, but the doc examples doesnt work for me
my services.yml
services:
app.form.registration:
class: AppBundle\Form\RegistrationFormType
tags:
- { name: form.type, alias: app_user_registration }
app.locale_listener:
class: AppBundle\EventListener\LocaleListener
arguments: ["%kernel.default_locale%"]
tags:
- { name: kernel.event_subscriber }
route
register:
pattern: /register
defaults: { _controller: AppBundle:Registration:register }
registration controller
namespace AppBundle\Controller;
use Symfony\Component\HttpFoundation\RedirectResponse;
use FOS\UserBundle\Controller\RegistrationController as BaseController;
use Symfony\Component\HttpFoundation\Request;
use FOS\UserBundle\FOSUserEvents;
use FOS\UserBundle\Event\GetResponseUserEvent;
class RegistrationController extends BaseController
{
public function registerAction(Request $request)
{
$form = $this->container->get('app.registration.form');
$formHandler = $this->container->get('fos_user.registration.form.handler');
$confirmationEnabled = $this->container->getParameter('fos_user.registration.confirmation.enabled');
$process = $formHandler->process($confirmationEnabled);
if ($process) {
$user = $form->getData();
/*****************************************************
* Add new functionality (e.g. log the registration) *
*****************************************************/
$this->container->get('logger')->info(
sprintf('New user registration: %s', $user)
);
if ($confirmationEnabled) {
$this->container->get('session')->set('fos_user_send_confirmation_email/email', $user->getEmail());
$route = 'fos_user_registration_check_email';
} else {
$this->authenticateUser($user);
$route = 'fos_user_registration_confirmed';
}
$this->setFlash('fos_user_success', 'registration.flash.user_created');
$url = $this->container->get('router')->generate($route);
return new RedirectResponse($url);
}
return $this->render('blog/register.html.twig', array(
'form' => $form->createView(),
));
}
}
registration form type
namespace AppBundle\Form;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use FOS\UserBundle\Form\Type\RegistrationFormType as BaseController;
class RegistrationFormType extends BaseController
{
/**
* #param string $class The User class name
*/
public function __construct($class)
{
parent::__construct($class);
}
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('username', null, array('label' => 'form.username', 'translation_domain' => 'FOSUserBundle'))
->add('plainPassword', 'repeated', array(
'type' => 'password',
'options' => array('translation_domain' => 'FOSUserBundle'),
'first_options' => array('label' => 'form.password'),
'second_options' => array('label' => 'form.password_confirmation'),
'invalid_message' => 'fos_user.password.mismatch',
))
->add('email', 'email', array('label' => 'form.email', 'translation_domain' => 'FOSUserBundle'))
->add('phone', null, array('label' => 'form.phone', 'translation_domain' => 'FOSUserBundle'))
->add('gender', null, array(
'choices' => array(
'morning' => 'Morning',
'afternoon' => 'Afternoon',
'evening' => 'Evening',
)
))
->add('about', null, array('label' => 'form.about', 'type' => 'textarea', 'translation_domain' => 'FOSUserBundle'))
;
}
}
On /register page im getting error - You have requested a non-existent service "app.registration.form".
What is the right solution to override default register form to my custom?
Thank you