How many dies in the set? I believe you may have the deluxe set, which comes with a collet sizing die, full length sizing die, and a seating die. Or you have the set I have that comes with a FL sizing die, seater, and crimp.
In the pic above, the die on the right is a crimp die, the left is the seat die. The one not shown would be a sizing die, either FL or collet.
I have a Lee catalog in front of me, on the instructions that came with your dies is the part#, it will be on the top left corner of the instructions on the same page that says Lee Reloading Dies. You will have 90880, 90508, 90715, or 90615. give me the number, I will tell you what you have for dies. Also, if you know if you bought pacesetter, deluxe, collet, or RGB dies that will help as well.
Or post a pic and that will make it very easy, just take a pic of all your dies.
Unless you bought them used, as you may have a seat and crimp die and a dead length seating die, but they don't come together in a set from lee.