When new email arrives im extracting subject values and storing it in the list item
Incoming email sample
Subject:USA,Client9
So if they are using same subject values but different attachments then it should update document library for the new attachment but at list item level it should not create new item as per below, so how to prevent duplicity in this context.
Flow details
How to prevent duplicates in the list item and in my case if the subject has same values then how to restrict those items