VCF Operations 9.0.x
The Oracle Database is configured with the VM short name in the HOST_NAME property for the instance.
The VCF Operations Management Pack for Oracle Database attempts to match the General|Host Name property that is collected from the Oracle Database Instance to the Configuration|Name property of a VM (the match ignores character case.)
Review Oracle documentation for steps to update the HOST_NAME property of the database instance to use the VM's FQDN.