In this post, you’ll learn more about the Oracle ErrorORA-19973: flashback database is not enabled with the details on why you receive this error and the possible solution to fix it.
Oracle Error Description
ORA-19973: flashback database is not enabled
Reason for the Error ORA-19973: flashback database is not enabled
Physical standby transition to snapshot standby required only one instance left running if flashback database logging was not enabled.
How to fix the Error ORA-19973: flashback database is not enabled ?
You can fix this error in Oracle by following the below steps
Shutdown all but one instance, then retry the command.