Ошибка кода

Contoller.php

<?php

public function changePassAction($slug)
    {
        $qb = $this->getDoctrine()->getConnection()->createQueryBuilder();
        $qb->select('*')->from('user');
        $qb->where('username = :slug');
        $qb->orWhere('id = :slug');
        $qb->setParameter(':slug',$slug );

        $row = $qb->execute()->fetch();

        $form = $this->createFormBuilder()
            ->add('pass_check', TextType::class,array('label' => 'Старый пароль'))
            ->add('pass', TextType::class,array('label' => 'Новый пароль'))
            ->add('repeat_pass', TextType::class,array('label' => 'Повторите пожалуйста пароль'))
            ->add('save', SubmitType::class, array('label' => 'Изменить пароль'))
            ->getForm();

        return $this->render("WebBundle:Account:changepass.html.twig",
            array(
                'username'=> $row['username'],
                'form' => $form->createView(),
                'action' => $this->generateUrl(
                    'changePass',
                    array('slug' => $row['id'])),
                'method' => 'POST',
            ));

    }

form.tiwg.html

{% extends "::base.html.twig" %}
{% block body %}
    <h1>Смена пароля у пользователя {{ username }}</h1>
    {{ form_start(form, {'action': path('changePass'), 'method': 'POST'}) }}
    {{ form_widget(form) }}
    {{ form_end(form) }}
{% endblock %}