How to make Item Description For Uniqueness

Hi,

I defining Data Quality Attribute on Item description but description is not showing up when I create item with same description. Also I did this step up in the below but it did not work. Could you help me why I can't description is not show up?

1.Navigate to Setup and Maintenance

2.Select Product Management Offering

3.Select Item functional area-> 'Manage Operational Attribute Groups'

4.Change Controlled At for attribute group=Main attribute=item description from Org level to master level

Thanks,

Beste