I know there are several question regarding this but still can’t get the answer and still got the problem.

So basically i am using Ci4 routing
I have my controller found under:

app
-Controllers
--Admin
---Access
----Departments.php

I made the route in the routes.php as follows:

$routes->group('admin', static function($routes) {
    $routes->group('access', static function($routes) {
        $routes->group('departments', static function($routes) {
            $routes->get('/', 'adminAccessDepartments::index');
        });
    });
});

I have tried also:

$routes->group('admin/access/departments', static function($routes) 
{
    $routes->get('/', 'adminAccessDepartments::index');
});

And i am still getting the 404 error:

Controller or its method is not found: AppControllersadminAccessDepartments::index

And yes the controller has a method called index:

<?php

namespace AppControllers;
class Departments extends BaseController
{
    public function index()
    {
        echo 'departments';
    }
}