Internal Server Error notification returned while trying to decorate a SWAG plugin service

Shopware 6 (English)
,
1

Trying to decorate a PayPal service:

<service id="TestPlugin\Service\Client\PayPalClientFactory" decorates="Swag\PayPal\RestApi\Client\PayPalClientFactory">
    <argument type="service" id="Swag\PayPal\RestApi\Client\CredentialsClientFactory.inner" />
</service>

but i get the following error notification when installing the TestPlugin:

The service "TestPlugin\Service\Client\PayPalClientFactory" has a dependency on a non-existent service "Swag\PayPal\RestApi\Client\CredentialsClientFactory.inner". 
Did you mean one of these: 
"Swag\PayPal\RestApi\Client\CredentialsClientFactory", "Swag\PayPal\RestApi\Client\TokenClientFactory"

Below is the decorating class:

<?php

namespace TestPlugin\Service\Client;

use Swag\PayPal\RestApi\Client\PayPalClientFactoryInterface;
use Swag\PayPal\RestApi\Client\PayPalClientInterface;
use Swag\PayPal\RestApi\PartnerAttributionId;

class PayPalClientFactory implements PayPalClientFactoryInterface
{
    /**
     * @var PayPalClientFactoryInterface
     */
    private PayPalClientFactoryInterface $decoratedService;

    /**
     * @param PayPalClientFactoryInterface $decoratedService
     */
    public function __construct(PayPalClientFactoryInterface $decoratedService)
    {
        $this->decoratedService = $decoratedService;
    }

    public function getDecorated(): PayPalClientFactoryInterface
    {
        return $this->decoratedService;
    }

    public function getPayPalClient(?string $salesChannelId, string $partnerAttributionId = PartnerAttributionId::PAYPAL_CLASSIC): PayPalClientInterface
    {
        return $this->getDecorated()->getPayPalClient($salesChannelId, $partnerAttributionId);
    }

    //...
}
2

Not sure, but I think that you only can use the .inner on the same Class that is decorated.

Swag\PayPal\RestApi\Client\PayPalClientFactory.inner