title: Class does not implement “Symfony\Component\Form\FormTypeInterface”
body: <p>I create a form to modify my data, but when I want to access my form, I get this error :</p>
  
  <blockquote>
    <p>Could not load type "App\Entity\Clients": class does not implement
    "Symfony\Component\Form\FormTypeInterface".</p>
  </blockquote>
  
  <h2>ClientsEntity :</h2>
  
  <pre><code>&lt;?php
  
  namespace App\Entity;
  
  use Doctrine\ORM\Mapping as ORM;
  
  /**
   * @ORM\Entity(repositoryClass="App\Repository\ClientsRepository")
   * @ORM\Table(name="app_clients")
   */
  class Clients
  {
      /**
       * @var int
       *
       * @ORM\Id
       * @ORM\GeneratedValue
       * @ORM\Column(type="integer")
       */
      private $id;
  
      /**
       * @var string
       *
       * * @ORM\Column(type="string", length=180, unique=true)
       */
      private $name;
  
      public function getId(): ?int
      {
          return $this-&gt;id;
      }
  
      public function setName(string $name): void
      {
          $this-&gt;name = $name;
      }
  
      public function getName(): ?string
      {
          return $this-&gt;name;
      }
  
      public function __toString(): string
      {
          return $this-&gt;name;
      }
  }
  </code></pre>
  
  <h2>ClientType :</h2>
  
  <pre><code>&lt;?php
  
  namespace App\Form;
  
  use App\Entity\Clients;
  use Symfony\Component\Form\AbstractType;
  use Symfony\Component\Form\FormBuilderInterface;
  use Symfony\Component\OptionsResolver\OptionsResolver;
  
  
  class ClientType extends AbstractType
  {
      public function buildForm(FormBuilderInterface $builder, array $options)
      {
            $builder
                -&gt;add('name', null, array(
                    'label'    =&gt; 'Domaine du client',
                    'required' =&gt; true,
                ))
            ;
      }
  
      public function configureOptions(OptionsResolver $resolver)
      {
          $resolver-&gt;setDefaults([
              'data_class' =&gt; Clients::class,
              'name' =&gt; null
          ]);
      }
  }
  </code></pre>
  
  <h2>ClientsController :</h2>
  
  <pre><code>   /**
       * @Route("/edit/{id}", name="support_admin_client_edit", methods={"GET","POST"})
       */
      public function edit(Request $request, Clients $clients): Response
      {
          $form = $this-&gt;createForm(ClientType::class, $clients);
          $form-&gt;handleRequest($request);
  
          if ($form-&gt;isSubmitted() &amp;&amp; $form-&gt;isValid()) {
              $this-&gt;getDoctrine()-&gt;getManager()-&gt;flush();
  
              return $this-&gt;redirectToRoute('support_admin_client_index', [
                  'id' =&gt; $clients-&gt;getId(),
              ]);
          }
  
          return $this-&gt;render('admin/ticketing/client/edit.html.twig', [
              'clients' =&gt; $clients,
              'form' =&gt; $form-&gt;createView(),
          ]);
      }
  </code></pre>
  
  <p>My form implements AbstractType so I do not see where my error comes from.
  Do you know where this message comes from?</p>