Soy is a common allergy/intolerance. It’s right near the top of the elimination diet (for figuring out your intolerances)

dairy, wheat, soy, eggs, nuts, and seafood/shellfish.

I’m not sure. I do have an insane amount of allergies and quite a few would be considered uncommon but I don’t think I’m allergic to soy. But either way it just destroys my stomach. Maybe it’s something you have to adjust to?