iProcurement, when I try to add item in my list I got an error that this item is already listed whil

When I choose an item to add it to my favorite list in the iProcurement, I got an error stating "This item is already listed in your Favorites List." although this item is not listed there.

If you check from the front end (from the iProcurement Personal Favorite, you will never find this item by if you search from the backend (Database) by running a small script you will find that this item and other items are already exist in the system. any one face this issue before?

The SQl which we use is:

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select distinct mtl.segment1, mtl.description, fL.item_description, fL.*