I'm not the person you were replying to but maybe the limit of using the websites like the ones I posted is you can't reuse the same face (at least not than I'm aware of).
So if you are in the UK and you upload 2 selfies from the site and the facial recognition pattern is different from each other, then the system which Reddit is using might reject it.
This is only a guess though.
Agreed. I hope more people leave that dumpster fire.