Phalcon\Mvc\Dispatcher\Exception: ActivityController handler class cannot be loaded

<?php
 
error_reporting(E_ALL);
 
$debug = new \Phalcon\Debug();
$debug->listen();
 
//try {
 
  include __DIR__ . "/../app/config/bootstrap.php";
 
  $application = new \Phalcon\Mvc\Application($di);
  echo $application->handle()->getContent();
 
/*
} catch (\Exception $e) {
  echo $e->getMessage();
}
*/