HYDME1350E The External authentication policy cannot be deleted.

Explanation
      The External authentication policy cannot be deleted because it is assigned to one or more clusters

  
Operator response
      You can delete the External authentication policy once it is not assigned to any cluster in the grid.
  To delete an External authentication policy, navigate to the Access->Security Settings page. Select any other defined authentication policy and
  assign it to the cluster using the External authentication policy. Then, you can proceed to Delete the External authentication policy.