An order to register a domain through the eNom registrar fails with the following error message:
Service Creation Failed: Domain registration failed - Registrar did not accept request.
In the corresponding domain subscription the following error is shown on the Service Status History tab:
Domain registration failed. Domain registration in Registrar failed: error no: 0 error text: Error from NSIRegister: Variable is undefined Err1: Invalid Domain Name or Nameserver Domain status:Prepared
Most likely the nameservers which PBA sends to eNom are not registered at the registrar and this is why they are considered as invalid.
Verify that nameservers are registered with registrar (eNom) properly and contact registrar to clarify the reason of the problem.
The nameservers which PBA sends to the registrar may be found in the 'Name Servers' section in the properties of the domain in question in the PBA Provider Control Panel: