I've migrated Plesk Domains to another Plesk node, terminated old Plesk Domain subscription that assigned the domain to old Plesk node. The following notification is shown when try to resolve the conflict:
Conflict Plesk domain is not registered in Parallels Business Automation - Standard. Plesk Domain DOMAIN.TLD Plesk client owning the current domain #CID Hardware Node NEW.PLESK.NODE Solution [x] Assign plesk domain to existing subscription.  Delete Plesk domain from the hardware node
I've verified that subscriptions with name DOMAIN.TLD is missing at
Top > Account Director > Subscription Manager > Subscriptions
Plesk Domain subscription that linked the domain to old Plesk node was not removed completely.
Contact Parallels Support to remove remain records.
IMPORTANT: before you create a subscription for a domain migrated to new Plesk node, it's needed to terminate old subscription with domain in old Plesk node.