Oracle Error Message
ORA-28071: The action is not valid.
Reason for the Error
The ACTION parameter to DBMS_REDACT.ALTER_POLICY was invalid.
Solution
Specify the ACTION parameter to DBMS_REDACT.ALTER_POLICY as one of the following values: DBMS_REDACT.MODIFY_EXPRESSION, DBMS_REDACT.MODIFY_COLUMN, DBMS_REDACT.ADD_COLUMN, or DBMS_REDACT.DROP_COLUMN.