Magento – Magento 2 – Core registry is empty

I created my custom controller that perform a post action, when there are some errors I need to send a param with a message to the view, but I can't use the messageManager class, because I need to put these error on a specific place.

I tried to add the error messages using \Magento\Framework\Registry on my Controller, then using my Block I get the registry and I tried to get the param on my .phtml but the variable is always null.

Here my controller: <vendor>\<module>\Controller\Account\LoginPost.php

<?php namespace <vendor>\<module>\Controller\Account; use Magento\Customer\Model\Account\Redirect as AccountRedirect; use Magento\Framework\App\Action\Context; use Magento\Customer\Model\Session; use Magento\Customer\Api\AccountManagementInterface; use Magento\Customer\Model\Url as CustomerUrl; use Magento\Framework\Exception\EmailNotConfirmedException; use Magento\Framework\Exception\AuthenticationException; use Magento\Framework\Data\Form\FormKey\Validator; class LoginPost extends \Magento\Customer\Controller\Account\LoginPost {
/**
 * @var \Magento\Framework\Registry
 */
protected $_coreRegistry;

/**
 * LoginPost constructor.
 * @param Context $context
 * @param Session $customerSession
 * @param AccountManagementInterface $customerAccountManagement
 * @param CustomerUrl $customerHelperData
 * @param Validator $formKeyValidator
 * @param AccountRedirect $accountRedirect
 * @param \Magento\Framework\Registry $registry
 */
public function __construct(
    Context $context,
    Session $customerSession,
    AccountManagementInterface $customerAccountManagement,
    CustomerUrl $customerHelperData,
    Validator $formKeyValidator,
    AccountRedirect $accountRedirect,
    \Magento\Framework\Registry $registry
) {
    parent::__construct($context,
        $customerSession,
        $customerAccountManagement,
        $customerHelperData,
        $formKeyValidator,
        $accountRedirect
    );
    $this->_coreRegistry = $registry;
}

/**
 * Login post action
 *
 * @return \Magento\Framework\Controller\Result\Redirect
 * @SuppressWarnings(PHPMD.CyclomaticComplexity)
 */
public function execute()
{

    $objectManager = \Magento\Framework\App\ObjectManager::getInstance();
    $baseUrl = $objectManager->get('Magento\Store\Model\StoreManagerInterface')->getStore()->getBaseUrl();
    $refererUrl = explode('?', $this->_redirect->getRefererUrl())[0];
    $previusPageNoError = str_replace($baseUrl, '', $refererUrl);
    $previusPage = $previusPageNoError . '?error=1';

    if ($this->getRequest()->isPost()) {
        $login = $this->getRequest()->getPost('login');
        if (!empty($login['username']) && !empty($login['password'])) {
            try {
                 // some code
            } catch (\Exception $e) {
                $message = __('My error message.');
                $this->_coreRegistry->register('message', $message);
                return $this->_redirect($previusPage);
            }
        } else {
            // some code
        }
    }
}}

Here my Block: <vendor>\<module>\Block\Form\Login.php

<?php namespace <vendor>\<module>\Block\Form; class Login extends \Magento\Customer\Block\Form\Login {

/**
 * @var \Magento\Framework\Registry
 */
protected $_coreRegistry;

/**
 * Login constructor.
 * @param \Magento\Framework\View\Element\Template\Context $context
 * @param \Magento\Customer\Model\Session $customerSession
 * @param \Magento\Customer\Model\Url $customerUrl
 * @param array $data
 */
public function __construct(
    \Magento\Framework\View\Element\Template\Context $context,
    \Magento\Customer\Model\Session $customerSession,
    \Magento\Customer\Model\Url $customerUrl,
    \Magento\Framework\Registry $registry,
    array $data = []
)
{
    parent::__construct(
        $context,
        $customerSession,
        $customerUrl,
        $data
    );
    $this->_coreRegistry = $registry;
}

/**
 * @return $this
 */
protected function _prepareLayout()
{
    return $this;
}

public function getRegistryMessage()
{
    return $this->_coreRegistry->registry('message');
}}

The return of the last method (getRegistryMessage()) is always null.