Data360 Govern

Hello, I would like to change the permission of an existing Site Navigation folder.

• I went to "Administration -> Setting".
• I highlighted the folder and selected "Edit". The "Edit Folder" screen was displayed.
• I selected the folder I wanted to change permission on and moved it to "Selected Folder Items". 
• I went to "Permissions" and selected the users/groups from the "Available Users/Groups". I moved the selected items to "Selected Users/Groups".
• Clicked on "Save Changes" and received the following message: 

  "Folder with name xxxxx already exists".

Please advise.