Self service Recovery for SQL Cluster

When enabling self service recovery for an Instance on a SQL Cluster you might run into the following error.

The specified SQL instance … is invalid or cannot be found (ID 32608). If a SQL instance exists with the specified name, use Get-Datasource –ProductionServer <ProductionServer> –Inquire cmdlet to refresh the information. Then retry the Operation.

Solution
SQL instances of a Cluster need to be added in a special way.
The convention is: FQDN of the Resource\SQLVirtualname\SQLInstance

Example
FQDN resource = (blackberry).c260.gp.wan
SQLVirtualname= C265
Instance name – BLACKBERRY

In the example above you need to specify the following SQL Server Instance: (Blackberry).c260.gp.wan\C265\BLACKBERRY