Help for Aimeos

If I set the porocess function to empty, as it says in the documentation https://aimeos.org/docs/Developers/Library/Service/Implement_delivery_provider I get an error like this "Argument 1 passed to Aimeos\MShop\Order\Item\Base\Base::addService() must implement interface Aimeos\MShop\Order\Item...

Thanks for the reply. I have tried removing the "process" function but, I have an error "Class Aimeos\MShop\Service\Provider\Delivery\MailRegalo contains 1 abstract method and must therefore be declared abstract or implement the remaining methods (Aimeos\MShop\Service\Provider\Deliver...

Hello, I need to add new fields to a service (deliveries). I have managed to show two fields with the $ feConfig configuration and access the Validation function. But I have stayed there. Where could I find an example that saves those fields in the database, and then when sending the emails I will a...