$username = "[USERNAME]";
    $password = "[PASSWORD]";
    $integrator_key = "[INTEGRATOR_KEY]";
    $host = "https://demo.docusign.net/restapi";
    $config = new Configuration(); -> en esta linea me da el fallo

"Autoload": {
     "Psr-4": {"": "src /"},
     "Classmap": ["app / AppKernel.php", "app / AppCache.php", "** src / AppBundle / juanitourquiza / pagopayphone / library" **]

composer update

//AppBundle/Services/PagotarjetaService.php
<?php
namespace AppBundleServices;

use BackendBundleEntityReservation;
use AppBundlejuanitourquizapagopayphonelibrary;

class PagotarjetaService{

 public $manager;

 public function __construct($manager) {
        $this->manager = $manager;
 }

 public function implementacion(){
    //tu codigo va aqui
    die("prueba");
 }
}

//app/services.yml
services:
#service_name:
#    class: AppBundleDirectoryClassName
#    arguments: ['@another_service_name', 'plain_value', '%parameter_name%']

app.pagotarjeta_service:
    class: AppBundleServicesPagotarjetaService
    arguments: ["@doctrine.orm.entity_manager"]

use AppBundleServicesPagotarjetaService;

$datospago=$this->get('app.pagotarjeta_service');
$datospago->implementacion();

prueba