Thanks for playing the game! Yeah that is a bug that can sometimes happen when you are "too close" to a big banana (but can't see it because for some reason some of them have a big area of influence), so it will always select that one and not the one right in front of you like it should. We didn't really have time to fix it. But reloading the game usually helps!
(The "boring choice" message always occurs when you try to change into a size you already have)