GET query doesn't work

I'm trying to use GET parameters in an URL (for example myserver.com/acontroler/?alias=q) but it doesn't work.

First it raised a BadRequestException #400 because it has disallowed characters, but adding "?&=" to $permittedURIChars returns a "404-Page not found" error.
What I'm doing wrong?  Shouldn't CI parse GET parameters by itself?

Can you show us your code so we can help?

Cannot reproduce.

app/Config/Routes.php

PHP Code:

<?php

use CodeIgniter\Router\RouteCollection;

$routes->get('acontroler', 'Home::index'); 


app/Controllers/Home.php

PHP Code:

<?php

namespace App\Controllers;

class Home extends BaseController
{
    public function index(): string
    {
        dd($this->request->getGet());
    }
} 


Code:

$ php spark serve

Navigate to http://localhost:8080/acontroler/?alias=q

Code:

$this->request->getGet() array (1)

    ⇄alias => string (1) "q"

⧉ Called from .../app/Controllers/Home.php:9 [dd()]

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