An order for a domain registration/transfer is stuck in "Provisioning" and the domain has the status Registered, Notifying. The Service Status History of the subscription shows:
Comment DNS Zone update was failed. Domain Status: Registered, Notifying<14 time(s) called.> Full Comment Parallels Operations Automation error #error_code #2005, extype_id #100, module_id #ResourceManagement, Resource 'DNS infrastructure' overusage attempt (subscription #<ID>, usage 2, limit 1)..
After some time, the order fails with an error:
Service Creation Failed: Cannot notify Name Servers on successful registration
This issue is caused by POA-82391 ("The DNS Hosting resource is used twice by the same domain, when initially a domain is created with external DNS hosting and then the DNS hosting is provisioned via PBA").
POA-82391 was fixed in Parallels Operations Automation (POA) 5.5.6.
As a workaround to complete order provisioning, increase the limit of the DNS resource in the subscription in POA (using the POA > Operations > Subscriptions > subscriptionID > Resources tab).