Symptoms
Application resource provisioning is failing with:
Value of key 'login' is required
Cause
The reason is invalid resources schema for your application.
/**
* @link("http://aps-standard.org/types/core/service-user/1.0")
* @required
*/
public $user;
If account is created from the store this is his first subscription no service users will be available and subscription provisioning will always fail because a service user is required for this application.
Resolution
Remove '@required' property and rebuild the application.