Cause
You tried to create a policy with the same name as an existing one.
You tried to create a policy with the same name as an existing one.
Use a different name or drop the existing policy.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12400.htm
https://community.oracle.com/message/3138255
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