Cakephp 3 EventManager无法在服务器上运行（它在服务器上没有监听器但在本地有监听器）

I'm trying to listen to "afterSave" callback using EventManager like this:

use Cake\Event\EventManager;

EventManager::instance()->on(
    'Model.afterSave', function ($event) {
        // do something    
    }
);

The problem: On local it works, and I can "do something" when a Model is saved, but on server it doesn't work.

What I found is that on local EventManager has listeners associated. As you can see:

use Cake\Event\EventManager;

debug(EventManager::instance());

object(Cake\Event\EventManager) {

    '_listeners' => [
        'Controller.shutdown' => '3 listener(s)',
        'Controller.initialize' => '2 listener(s)',
        'Controller.startup' => '2 listener(s)',
        'Controller.beforeRender' => '2 listener(s)',
        'View.beforeRender' => '2 listener(s)',
        'View.afterRender' => '2 listener(s)',
        'View.beforeLayout' => '2 listener(s)',
        'View.afterLayout' => '2 listener(s)',
        'View.beforeRenderFile' => '1 listener(s)',
        'View.afterRenderFile' => '1 listener(s)',
        'Model.afterSave' => '1 listener(s)'
    ],
    '_isGlobal' => true,
    '_generalManager' => '(object) EventManager'
}

But on server EventManager has no listeners:

use Cake\Event\EventManager;

debug(EventManager::instance());

object(Cake\Event\EventManager) {

    '_listeners' => [],
    '_isGlobal' => true,
    '_generalManager' => '(object) EventManager'
}

Why isn't working on server? Does it have anything related with the server configuration?

Many thanks!