Oracle Message ORA-16658 - unobserved fast-start failover configuration

ERRORunobserved fast-start failover configuration
CAUSEThe fast-start failover configuration was currently unobserved so failover was disallowed.
ACTIONMake sure the observer is running and has connectivity to both the primary and the target standby databases. Otherwise, disable fast-start failover to perform a failover in the absence of the observer process.