Yes, this is what confused me as well

Sorry, tried to respond to a post and it didn’t work. I expected にほんじん to be selected like one word, but since it looked like “に ほんじん” it was confusing.

You are right. “ほんじん” doesn’t make sense.
Separating words with spaces is carried out automatically. The system is not smart enough to deal with this sort of thing perfectly.