Error Auth

My appController:

$this->loadComponent('Auth', [
            'authenticate' => [
                'Form' => [
                    'fields' => ['username' => 'login', 'password' => 'senha'],
                    'passwordHasher' => [
                        'className' => 'Fallback',
                        'hashers' => [
                            'Default',
                            'Weak' => ['hashType' => 'sha1']
                        ]
                    ]
                ]
            ],
            'loginRedirect' => [
                'prefix' => 'admin',
                'controller' => 'Administracao',
                'action' => 'index'
            ],
            'logoutRedirect' => [
                'prefix' => false,
                'controller' => 'Paginas',
                'action' => 'index'
            ]
        ]);

My UsersController:

public function login(){
        if($this->request->is('post')){
      //debug($this->request->data(['username']['password']));exit; //this return my username and password(not md5) example felipe/123456
            $user = $this->Auth->identify();
            if($user){
                $this->Auth->setUser($user);
                if ($this->Auth->authenticationProvider()->needsPasswordRehash()) {
                    $user = $this->Users->get($this->Auth->user('id_usuario'));
                    $user->password = $this->request->data('password');
                    $this->Users->save($user);
                }
                return $this->redirect($this->Auth->redirectUrl());
            } else {
                $this->Flash->error(__('Username or password is incorrect'));
            }
        }
    }