ORA-16504
Cause
A request to create or import an Oracle Data Guard broker configuration is being made while connected to a database that is part of an existing configuration; or to add a second Oracle Data Guard broker configuration with the same configuration name or DRC_UNIQUE_ID as the local configuration.
Action
To create or import a new configuration, the existing configuration must be deleted. To add a second configuration, remove one of the configurations and re-create it, optionally with a different configuration name if it is the same as the first configuration. If the configurations have the same DRC_UNIQUE_IDs, the act of re-creating results in a different DRC_UNIQUE_ID. Once both configurations have different names and DRC_UNIQUE_IDs, reissue the ADD CONFIGURATION command.