cakephp - Error: userHelper could not be found in cakephp3.5.1 -

how fix issue

error: userhelper not found.

this search.ctp inside element called in default.ctp

<?php  echo $this->form->create(null, ['url' => ['controller' => 'users', 'action' => 'search']], array('type' => 'get'));  ?>    <?php  echo $this->form->input('username'); ?>  <?php echo $this->form->button('search', ['type' => 'submit']); ?> 

below search controller

public function search() {    $value = $this->request->getdata('username');     $results = $this->users->find('all', ['fields'=>[         'users.username',         'users.email',         'users.id',         'users.age',         'users.address',         'users.gender'       ],       'order' => 'users.id asc',       'conditions' => array(' username like' => "%".$value."%")    ]);    $this->set('user', $results);    $this->set('_serialize', ['user']); } 

search.ctp inside users

<?php    use cake\orm\tableregistry;     use cake\filesystem\folder;    use app\controller\appcontroller; ?> <?php foreach ($user $users): ?> <?php echo $this->users->username;?> <?php endforeach;?> 

what line inside loop? shouldn't be.

$this->users->username; 

i'm not sure returning array or object in cakephp 3.

but, i'm sure should that,

$users->username;  

or

$users['username'];