Module's array config in ENV does not work

Hi,
I have a module as

Code:

modules\Emails
modules\Emails\Config
modules\Emails\Controllers
modules\Emails

Now in my .env file I have following

Code:

Emails\Config\Email.sendTo = '[email protected]'
Emails\Config\Email.sendTo = Emails\Config\Email.settings.protocol = 'smtp'
Emails\Config\Email.settings.SMTPHost = 'smtp.example.com'
Emails\Config\Email.settings.SMTPPort = '345'

As per documentation  the $settings must be an array, but

PHP Code:

<?php namespace Emails\Config;

use CodeIgniter\Config\BaseConfig;

class Email extends BaseConfig
{

    public $sendTo; // works fine

    public $settings; // THIS IS NULL
} 


the variable $settings variable is empty;

I also tried something like

Code:

#-- Email --
Emails\Config\Email.settings = []
Emails\Config\Email.settings.protocol = 'smtp'

Still does not work.
What am I doing wrong here?