Symfony Event Listener

Hi I'm tring to do a Symfony event listener following this documentation: http://symfony.com/doc/2.8/cookbook/doctrine/event_listeners_subscribers.html

<?php

namespace FMAppBundleEventListener;

use DoctrineORMEventLifecycleEventArgs;
use FMAdminBundleEntityAddressBillingAddress;

class BillingAdressListener
{
    /**
     * @param LifecycleEventArgs $args
     */
    public function listenBillingAdress(LifecycleEventArgs $args)
    {
        $entity = $args->getEntity();

        if(!$entity instanceof BillingAddress){
            return;
        }

        $this->postPersist($args);
    }

    /**
     * @param LifecycleEventArgs $args
     */
    public function postPersist(LifecycleEventArgs $args)
    {
        $em = $args->getEntityManager();
        $billingAdress = $args->getEntity();

        dump($billingAdress); die();
    }
}

service.yml

billing_adress.listener:
        class: FMAppBundleEventListenerBillingAdressListener
        tags:
            - { name: doctrine.event_listener, event: listenBillingAdress }

But nothing is happening when I'm submitting a form with the BillingAddress object.

Did I do something wrong?