Slim 4. Пустой ответ parsed body

Форма signin.twig

<div class="content">
<h2>Log In</h2>
<form action="/signin-post" method="post">
    <div class="mb-3 frm-name">
  <label class="form-label">Name</label>
  <input type="name" id="name" class="form-control"  >
</div>
<div class="mb-3 frm-surname">
  <label   class="form-label">Surname</label>
  <input type="text" id="surname" class="form-control"  >
</div>
<div class="mb-3 frm-password">
  <label  class="form-label">Password</label>
  <input type="password" id="pass" class="form-control"  >
</div>


<input type="submit" class="btn btn-success" value="Send">
</form>
</div>
</div>

index.php

<?php 
use Slim\Factory\AppFactory;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Message\ResponseInterface; 
use Twig\Loader\FileSystemLoader;
use Twig\Environment;

$loader=new FileSystemLoader('templates');
$twig=new Environment($loader);

$app=AppFactory::create();

$app->addBodyParsingMiddleware();
$app->addRoutingMiddleware();
$app->addErrorMiddleware(true, true, true);
...
$app->post('/signin-post',function (ServerRequestInterface $request, ResponseInterface $response){
    $params=$request->getParsedBody();
    var_dump($params);
    return $response;
});
$app->run();
 ?>

Вывод

array(0) { }

Почему Slim не читает форму?