I can only think of 2 reasons why you have this problem.

1. SQL Server was installed into the cluster group 'CL2' on your PR server.

2. The 'SQL Network Name' was setup / configured incorrectly within the SQL Server cluster group

To confirm this, we will need a bit more information from Cluster Administrator.

What are the group names?

And more importantly, what resources are within each group?

e.g.

Group: CL1

Resources:

- Cluster Name

- Cluster IP

- Disk X

Also, could you please run the below query on both QA & PR and post the output? I am happy for you to change the server names as long you keep it consistent.

SELECT CAST( SERVERPROPERTY('InstanceName') AS NVARCHAR(128)) AS 'InstanceName'

SELECT CAST( SERVERPROPERTY('IsClustered') AS NVARCHAR(128)) AS 'IsClustered'

SELECT CAST( SERVERPROPERTY('MachineName') AS NVARCHAR(128)) AS 'MachineName'

SELECT CAST( SERVERPROPERTY('ServerName')AS NVARCHAR(128)) AS 'ServerName'

SELECT CAST( SERVERPROPERTY('ComputerNamePhysicalNetBIOS')AS NVARCHAR(128)) AS 'ComputerNamePhysicalNetBIOS'

I am hoping the output of the query will help explain the difference between instance name, virtual SQL server & server name