19” Lug Nut Size? 2 sizes?

I was doing my tire rotation on my Bolt EUV and thought I’d make sure I had everything for when I need to do it on my ‘25 Ioniq 5 Limited.
I pulled out some sockets and the 13/16 fit perfectly so I ordered an impact socket in that size. When I got it I slipped it on to check it and it didn’t fit. Doesn’t even feel close. I tried a different light on the same wheel and it fit perfectly. I checked all the lugs on every wheel. It turns out that the 13/16 only fits two lugs on each wheel (one wheel it’s 3). These are the stock 19” wheels and have never been touched (only 3k miles). Looking at all the lug nuts, they all look the same(visually). They are not security versions. Just regular six sided lug nuts.
What is the deal with this.