activation of user account

AccountActivationController.php

<?php

namespace App\Controller;

use App\Entity\User;
use App\Form\AccountActivationType;
use Doctrine\Persistence\ManagerRegistry;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\PasswordHasher\Hasher\UserPasswordHasherInterface;
use Symfony\Component\Routing\Annotation\Route;

class AccountActivationController extends AbstractController
{
    /**
     * @Route("/account_activation", name="account_activation")
     */
    public function index(
        Request $request,
        ManagerRegistry $doctrine,
        UserPasswordHasherInterface $passwordHasher
    ): Response {

        $form = $this->CreateForm(AccountActivationType::class);
        $form->handleRequest($request);

        if ($form->isSubmitted() && $form->isValid()) {
            $email = $form['email']->getData();
            $plainPassword = $form['code']->getData();
            $em = $doctrine->getManager();
            $userObj = $doctrine->getRepository(User::class)->findOneBy(['email' => $email]);
            $activation_hash = $userObj->getActivationHash();
            $user = new User();
            $user->setPassword($activation_hash);
            if ($passwordHasher->isPasswordValid($user, $plainPassword)) {
                $userObj->setActivated(true);
                $userObj->setActivationHash('');
                $em->persist($userObj);
                $em->flush();

                return $this->redirectToRoute('login');
            } else {
                //add error flash
            }

        }

        return $this->render('account_activation/index.html.twig', [
            'account_activation_form' => $form->createView(),
        ]);
    }
}