Symfony3 fosuserbundle overriding registrationForm - fosuserbundle

Question

I try to override the RegistrationBundle with adding a postal code.
But in the twig register form, when it loads, the postalcode field is not empty and there is written "user" in the
<input type="text">
And in the password field, it's not empty too
<input type="password">
This error occure when I am using "http://localhost:8000/app_dev.php/en/register/" but if I run another server like "http://localhost:8001/app_dev.php/en/register/" with port 8001, this error don't occure ! What is the matter ?
Could you explain me why ?
Hi Thanks for your comment. So, I overrided my FOSUserBundle Controller too ! Here is my Form :
private $em;
public function buildForm(FormBuilderInterface $builder, array $options)
{
$this->em = $options['em'];
$builder
->add('firstname', TextType::class)
->add('lastname', TextType::class)
->add('postalcode', TextType::class, array(
'attr'=> array('class'=>'postalcode form-control',
'maxlength'=>4,
'value'=>''))
)
->add('city', ChoiceType::class, array(
'attr'=>array('class'=>'city form-control')))
->add('conditions', CheckboxType::class, array('required' => true))
;
$city = function(FormInterface $form, $codepostal){
$localitestofind = $this->em->findBy(array('codepostal'=>$codepostal));
$localites = array();
if($localitestofind)
{
foreach($localitestofind as $localitetofind)
{
$localites[$localitetofind->getNom()] = $localitetofind->getNom();
}
}
$form->add('city', ChoiceType::class, array(
'attr'=>array('class'=>'city form-control'),
'choices'=> $localites));
};
$builder->get('postalcode')->addEventListener(FormEvents::POST_SUBMIT, function(FormEvent $event) use ($city){
$city($event->getForm()->getParent(), $event->getForm()->getData());
});
}
Your right, but I don't know why my browser autocomplete both fields. I removed the cache of the browser, I removed cookies, ... And I don't have this problem on an other port (8000 vs 8001)
Thanks a lot for helping