Change language dynamically CI 4.4.6

I'm trying to change the language of my app.

I've tried inside the BaseController in the initController method in several ways

PHP Code:

$lingua = session('lingua');
config('App')->defaultLocale = $lingua; 


or

PHP Code:

$lingua = session('lingua');
(!isset($lingua)) ? $this->request->setLocale('it') : $this->request->setLocale(session('lingua')); 


or

PHP Code:

$lingua = session('lingua');
config('App')->defaultLocale = $lingua;
(!isset($lingua)) ? $this->request->setLocale('it') : $this->request->setLocale(session('lingua')); 


If I try to print these variables on the screen I receive:
echo session('language'); returns "en"
echo config('App')->defaultLocale; returns "en"
echo $this->request->getLocale(); return 'it'
If I manually change the value of public string $defaultLocale to 'en' or 'it' everything works and I see the app in the desired language

What should I do to be able to change the language dynamically?

I don't need the URL changed.

I am using the following code:
In the top navigation, I have a dropdown menu:

Code:

<ul aria-labelledby="dropdownSubMenu1" class="dropdown-menu border-0 shadow">
     <li><a href="<?= base_url(); ?>/lang/set_language/en/<?= str_replace('/', '~', current_url()); ?>" class="dropdown-item"><?=lang('Language.English')?> </a></li>
     <li><a href="<?= base_url(); ?>/lang/set_language/nl/<?= str_replace('/', '~', current_url()); ?>" class="dropdown-item"><?=lang('Language.Dutch')?> </a></li>
</ul>

I have a controller in a folder language with the following code to set the language:

PHP Code:

public function set_language()
    {
        // Get the language id
        $uri = current_url(true);
        $total = $uri->getTotalSegments();
        // get the language id
        $id = $uri->getSegment($total-1);

        // Get the url to go to after this
        $redirect = str_replace ("~", "/", $uri->getSegment($total));
        $session = session();
        $session->remove('language');
        $session->set('language', $id);
        return redirect()->to($redirect);
    } 


This changes the language without changing the url.

I am using the following code:
In the top navigation, I have a dropdown menu:

Code:

<ul aria-labelledby="dropdownSubMenu1" class="dropdown-menu border-0 shadow">
     <li><a href="<?= base_url(); ?>/lang/set_language/en/<?= str_replace('/', '~', current_url()); ?>" class="dropdown-item"><?=lang('Language.English')?> </a></li>
     <li><a href="<?= base_url(); ?>/lang/set_language/nl/<?= str_replace('/', '~', current_url()); ?>" class="dropdown-item"><?=lang('Language.Dutch')?> </a></li>
</ul>

I have a controller in a folder language with the following code to set the language:

PHP Code:

public function set_language()
    {
        // Get the language id
        $uri = current_url(true);
        $total = $uri->getTotalSegments();
        // get the language id
        $id = $uri->getSegment($total-1);

        // Get the url to go to after this
        $redirect = str_replace ("~", "/", $uri->getSegment($total));
        $session = session();
        $session->remove('language');
        $session->set('language', $id);
        return redirect()->to($redirect);
    } 


This changes the language without changing the url.

I don't see where you set the value of the app language, I only see a setting of a session value that I already have, my problem is that I can't change the language or I can't change the defaultLocale value, if I I do it by hand works correctly but I can't modify it from code, i.e. based on the value of session('lang').

I don't use the URL like /home/en, I don't need it, I just need to be able to change the language of everything

Sorry,
My answer was incomplete. The default language is set in the initController function in the BaseController:

PHP Code:

$session = \Config\Services::session();
$language = \Config\Services::language();
$locale = $this->request->getLocale();
$currentLanguage = $session->get('language');
if(!$currentLanguage):
    $session->set('language', $locale);
endif;
$language->setLocale($session->language); 


Hope this helps

Sorry,
My answer was incomplete. The default language is set in the initController function in the BaseController:

PHP Code:

$session = \Config\Services::session();
$language = \Config\Services::language();
$locale = $this->request->getLocale();
$currentLanguage = $session->get('language');
if(!$currentLanguage):
    $session->set('language', $locale);
endif;
$language->setLocale($session->language); 


Hope this helps

Thanks, I think I solved it