Problem with load lib

Hi, 
I need to use this library: https://github.com/PayU-EMEA/openpayu_php
so I installed it with this command:

composer require openpayu/openpayu

In controller I have this code: 

PHP Code:

<?php

namespace App\Controllers;

use CodeIgniter\Controller;
use OpenPayU_Configuration;

class Home extends Controller {

    public function index() {
      
      OpenPayU_Configuration::setEnvironment('sandbox');
      
    }

} 


I have this error:

Class "OpenPayU_Configuration" not found

Should I add something to Config/Autoload.php?


@edit: 
I added this to config/Autoload.php:

PHP Code:

public $psr4 = [
        APP_NAMESPACE          => APPPATH, // For custom app namespace
        'Config'                => APPPATH . 'Config',
        'PHPMailer\PHPMailer'  => ROOTPATH . 'vendor/phpmailer/phpmailer/src',
        'OpenPayU'              => ROOTPATH . 'vendor/openpayu/openpayu/lib/OpenPayU'
]; 


In Controller I have:

PHP Code:

use OpenPayU\Configuration as OpenPayU_Configuration; 


and error is still.

Solution

In controller I have:

PHP Code:

use OpenPayU_Configuration;
use OpenPayU_Order;

...

$openPayUConfig = new OpenPayU_Configuration(); 
$openPayUConfig->setEnvironment('sandbox'); 


and it works!