I created subscription, but provisioning failed on task "Create the blank subscription" with the following error:
Duplicate key violates unique constraint 'plesk_subscriptions_pk0' while executing ' INSERT INTO plesk_subscriptions (ext_id, is_brand) VALUES ( ?, ? )'.
Service Template misconfiguration. It is not possible to use two resources based on "Subscription Resource class" in one service template.
Go to service template which was used for subscription creation:
Products > Service Templates > template name > Resources
Make sure that resource "Number of domains" and "Number of subdomains" is not mentioned twice, if so - then it is needed to remove one of resources based on "Subscription Resource class".