Actually it’s happened a few times. I remember that I had a tie with someone and we were both listed twice. Not only that but sometimes when you check INCIT wins you will see a win listed twice. Not that you won the same picture with the same entry, it’s the exact same one (I don’t reuse my submissions). But I’m not sure if it’s constant, I think I looked for doubles once and didn’t see them. I’m not sure if that’s linked to the OP’s “problem”, but I’d thought I’d mention it.