Gravity Forms duplicate prevention based on select fields

I have a form used to enter data and multiple people use it. Is there a way to prevent duplicates based on only a few select fields and not all? In the form, one of our fields is an initial text field, where the user puts in their initials. In a case were two people are unintentionally entering the same data, this initial field will still be different. Right now we export entries and use a pivot table to find duplicates. Any suggestions to prevent different people from entering the same data? Is there a plug in that notifies the user if they may be entering a duplicate entry?

Thanks!