Model could not be loaded

Hi world I'm trying to get the tutorial 7 code work. but when i implement curl -i -X GET xxx, i get the error like below

PHP Fatal error: Uncaught Phalcon\Mvc\Model\Exception: Model 'Store\Toys\Robots' could not be loaded in /var/www/html/my-rest-api/index.php:48\nStack trace:\n#0 [internal function]: Phalcon\Mvc\Model\Manager->load('Store\\Toys\\Robo...', true)\n#1 [internal function]: Phalcon\Mvc\Model\Query->_prepareSelect()\n#2 [internal function]: Phalcon\Mvc\Model\Query->parse()\n#3 [internal function]: Phalcon\Mvc\Model\Query->execute()\n#4 /var/www/html/my-rest-api/index.php(48): Phalcon\Mvc\Model\Manager->executeQuery('SELECT * FROM S...')\n#5 [internal function]: Closure->{closure}()\n#6 /var/www/html/my-rest-api/index.php(263): Phalcon\Mvc\Micro->handle()\n#7 {main}\n thrown in /var/www/html/my-rest-api/index.php on line 48

my index.php is below:

<?php use Phalcon\Loader; use Phalcon\Mvc\Micro; use Phalcon\Di\FactoryDefault; use Phalcon\Db\Adapter\Pdo\Mysql as PdoMysql; use Phalcon\Http\Response;

$loader = new Loader();

$loader->registerNamespaces( [ "Store\Toys" => DIR . "/models/", ] );

$loader->register();

$di = new FactoryDefault();

//DB setup $di->set( "db", function(){ return new PdoMysql( [ "host" => "localhost", "username" => "", "password" => "", "dbname" => "robotics", ] ); } );

$app = new Micro($di);

$app->get('/', function(){ echo "Restful API Phalcon"; });

//Retrives all robots $app->get( "/api/robots", function () use ($app) {

$phql = "SELECT * FROM Store\\Toys\\Robots ORDER BY name";

$robots = $app->modelsManager->executeQuery($phql);

$data = [];

foreach ($robots as $robot) {
  $data[] = [
    "id" => $robot->id,
    "name" => $robot->name,
  ];
}
echo json_encode($data);

} );

//Searches for robots with $name in their name $app->get( "/api/robots/search/{name}", function ($name) use ($app){ $phql = "SELECT * FROM Store\Toys\Robots WHERE name LIKE :name: ORDER BY name";

$robots = $app->modelsManager->executeQuery($phql,
[
  "name" => "%" . $name . "%"
]

);

$data = [];

foreach ($robots as $robot) { $data[] = [ "id" => $robot->id, "name" => $robot->name ]; } echo json_encode($data); } );

//Retrieves robots based on primary key $app->get( "/api/robots/{id:[0-9]+}", function($id) use ($app){ $phql = "SELECT * FROM Store\Toys\Robots WHERE id = :id:";

$robots = $app->modelsManager->executeQuery($phql,

[ "id" => $id, ] )->getFirst;

$response = new Response();

if ($robot === false) { $response->setJsonContent( [ "status" =>"NOT-FOUND" ] ); } else { $response->setJsonContent( [ "status"=>"FOUND", "data"=> [ "id" => $robot->id, "name" => $robot->name ] ] ); } return $response; } );

//Adds a new robot $app->post( "/api/robots", function() use ($app){ $robot = $app->request->getJsonRawBody();

$phql = "Insert into Store\\Toys\\Robots (name, type, year) VALUES(:name:, :type:, :year:)";

$status = $app->modelsManager->executeQuesry(
  $phql,
  [
    "name" => $robot->name,
    "type" => $robot->type,
    "year" => $robot->year,
  ]
);

$response = new Response();

if ($status->success() === true) {
  $response->setStatusCode(201,"created");

  $robot->id = $status->getModel()->id;

  $response->setJsonContent(
    [
      "status" => "OK",
      "data" => $robot,
    ]
  );
} else{
  //change the http status
  $response->setStatusCode(409, "Conflict");

  $errors = [];

  foreach ($status->getMessages() as $message) {
    $error[] = $message->getMessage();
  }

  $response->setJsonContent(
    [
      "status" => "ERROR",
      "messages"=>$errors,
    ]
  );
}
return $response;

} );

$app->put( "/api/robots/{id:[0-9]+}", function($id) use ($app) { $robot = $app->request->getJsonRawBody();

       $phql = "UPDATE Store\\Toys\\Robots SET name = :name:, type = :type:, year = :year: WHERE id = :id:";

       $status = $app->modelsManager->executeQuery(
           $phql,
           [
               "id"   => $id,
               "name" => $robot->name,
               "type" => $robot->type,
               "year" => $robot->year,
           ]
       );

       // Create a response
       $response = new Response();

       // Check if the insertion was successful
       if ($status->success() === true) {
           $response->setJsonContent(
               [
                   "status" => "OK"
               ]
           );
       } else {
           // Change the HTTP status
           $response->setStatusCode(409, "Conflict");

           $errors = [];

           foreach ($status->getMessages() as $message) {
               $errors[] = $message->getMessage();
           }

           $response->setJsonContent(
               [
                   "status"   => "ERROR",
                   "messages" => $errors,
               ]
           );
       }

       return $response;

} );

$app->delete( "/api/robots/{id:0-9+}", function($id) use ($app){ $phql = "DELETE FROM Store\Toys\Robots WHERE id = :id:";

       $status = $app->modelsManager->executeQuery(
           $phql,
           [
               "id" => $id,
           ]
       );

       // Create a response
       $response = new Response();

       if ($status->success() === true) {
           $response->setJsonContent(
               [
                   "status" => "OK"
               ]
           );
       } else {
           // Change the HTTP status
           $response->setStatusCode(409, "Conflict");

           $errors = [];

           foreach ($status->getMessages() as $message) {
               $errors[] = $message->getMessage();
           }

           $response->setJsonContent(
               [
                   "status"   => "ERROR",
                   "messages" => $errors,
               ]
           );
       }
       return $response;

} );

$app->handle();

?>