! Duplicates not working

[kxap]

I'm performing a search using '!' in Filemaker on last names, and I'm coming up with some duplicates and some that are not. Is that a bug?

I'm using FM v5.03

[-Queue-]

Have you sorted by last name after obtaining your found set? There are surely duplicate last names, but that doesn't mean they will show in that order or that you have true duplicate records where the first, middle, AND last name, along with address (or whatever) are the same.