Change password symfony

// CurrentUserController

    /**
     * @Rest\Route("/users/me/password", name="mc_change_user_password")
     * @Method({"POST"})
     *
     * @param UserInterface $user
     * @param Request $request
     * @return mixed
     * @throws \Doctrine\ORM\OptimisticLockException
     */
    public function changePasswordAction(UserInterface $user, Request $request)
    {
        $newPassword = $request->query->get('password');
        $username = $user->getUsername();

        $storedUser = $this->em->getRepository(User::class)->findOneBy(['username' => $username]);

        $storedUser->setPlainPassword($newPassword);

        dump($storedUser);
        $this->userManager->updatePassword($storedUser);
        $this->userManager->updateUser($storedUser);

        return View::create($storedUser, Response::HTTP_NO_CONTENT);

    }