To create a flashback restore point, you must be using FRA and flashback must be turned on.
Check to see if flashback is turned on with the following:
Enabling Flashback Database
Step 1 . Set the parameters
Step 2 . Shutdown the database
Step 3 . Startup mount the database (one node) and turn on Flash Back
Step 4 . Make Sure Flashback is Turned ON and shutdown the instance.
Step 5 . Start up RAC instances
Create Restore Point
Recover Dataabse with Restore Point