On update don't update an entity replace it - symfony

Question

I have a Branch entity that has an Address entity, one address can be link to many other types of entities, what I want to do is when I edit the Address in the Branch entity instead of editing the address with the new data I want to create a new Address entity and attach it to the Branch, what is happening right now is that its editing the address, the problem with this is that I have other entities linked to that address.
This is my form:
class MBBranchType extends AbstractType{
protected $em;
function __construct(EntityManager $em){
$this->em = $em;
}
/**
* #param FormBuilderInterface $builder
* #param array $options
*/
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('branchName')
->add('branchCode')
->add('destiny', 'entity', array(
'class' => 'ATRBundle:Destiny',
'empty_value' => '-- Seleccione --',
'mapped' => true,
'query_builder' => function(EntityRepository $er){
return $er->createQueryBuilder('d')
->orderBy('d.destinyDesc', 'ASC');
}))
->add('startOperation', 'text')
->add('stopOperation', 'text', array('required' => ''))
->add('authorizationL1', 'checkbox', array('required' => ''))
->add('authorizationL2', 'checkbox', array('required' => ''))
->add('authorizationL3', 'checkbox', array('required' => ''))
->add('address', new AddressType($this->em, new Address()), array('required' => ''))
->add('active', 'checkbox', array('required' => ''));
$builder->get('startOperation')->addModelTransformer(new StringToDateTransformer());
$builder->get('stopOperation')->addModelTransformer(new StringToDateTransformer());
}
/**
* #param OptionsResolverInterface $resolver
*/
public function setDefaultOptions(OptionsResolverInterface $resolver)
{
$resolver->setDefaults(array(
'data_class' => 'MB2\ATRBundle\Entity\MBBranch'
));
}
/**
* #return string
*/
public function getName()
{
return 'mb2_atr_mb_branch';
}
}
This is my Action
public function editMBBranchAction()
{
$id = $this->request->query->get('id');
$entity = $this->em->getRepository('ATRBundle:MBBranch')->find($id);
$form = $this->createForm(new MBBranchType($this->getDoctrine()->getManager()), $entity);
$form->handleRequest($this->request);
if ($form->isValid()) {
if($entity instanceof MBBranch){
$addressEntity = $this->em->getRepository('ATRBundle:Address')->findOneBy(
array('street'=>(string)$entity->getAddress()->getStreet()
, 'exteriorNum' => $entity->getAddress()->getExteriorNum();
, 'interiorNum' => $entity->getAddress()->getInteriorNum();
, 'settlment' => $entity->getAddress()->getSettlment()
)
);
if($addressEntity instanceof \MB2\ATRBundle\Entity\Address){
$entity->setAddress($addressEntity);
}else{
$otherAddress = new Address();
$otherAddress->setStreet($entity->getAddress()->getStreet());
$otherAddress->setExteriorNum($entity->getAddress()->getExteriorNum());
$otherAddress->setInteriorNum($entity->getAddress()->getInteriorNum());
$otherAddress->setSettlment($entity->getAddress()->getSettlment());
$entity->setAddress($otherAddress);
}
$this->em->flush();
}
return $this->redirect($this->generateUrl('admin', array('action' => 'list', 'entity' => $this->entity['name'])));
}
return $this->render($this->entity['templates']['edit'], array(
'form' => $form->createView(),
'entity' => $entity,
));
}
As you can see it checks if the new Address entity exist, if it does exist it sets it on the $entity->setAddress($addressEntity);, If it does not exist it created a new Address() and sets the values, This does work, it created a new Address and saves it on the table, but for some reason it also updateing the old Address entity.

Answer 1

I found the solution
I added a $this->em->detach($entity->getAddress()); before attaching a new Address, please see example.
public function editMBBranchAction()
{
$id = $this->request->query->get('id');
$entity = $this->em->getRepository('ATRBundle:MBBranch')->find($id);
$form = $this->createForm(new MBBranchType($this->getDoctrine()->getManager()), $entity);
$form->handleRequest($this->request);
if ($form->isValid()) {
if($entity instanceof MBBranch){
$this->em->detach($entity->getAddress());
$addressEntity = $this->em->getRepository('ATRBundle:Address')->findOneBy(
array('street'=>(string)$entity->getAddress()->getStreet()
, 'exteriorNum' => $entity->getAddress()->getExteriorNum();
, 'interiorNum' => $entity->getAddress()->getInteriorNum();
, 'settlment' => $entity->getAddress()->getSettlment()
)
);
if($addressEntity instanceof \MB2\ATRBundle\Entity\Address){
$entity->setAddress($addressEntity);
}else{
$otherAddress = new Address();
$otherAddress->setStreet($entity->getAddress()->getStreet());
$otherAddress->setExteriorNum($entity->getAddress()->getExteriorNum());
$otherAddress->setInteriorNum($entity->getAddress()->getInteriorNum());
$otherAddress->setSettlment($entity->getAddress()->getSettlment());
$entity->setAddress($otherAddress);
}
$this->em->flush();
}
return $this->redirect($this->generateUrl('admin', array('action' => 'list', 'entity' => $this->entity['name'])));
}
return $this->render($this->entity['templates']['edit'], array(
'form' => $form->createView(),
'entity' => $entity,
));
}