Maybe it's a neurological thing (coordination) or something with her eyesight that isn't apparent. When we gave our bird treats we would give her a treat from one side and she wouldn't see it, when we put it on her other side she would go for it. My birds eyes looked ok just that one pupil on one side of her head was larger than the one on the other side but as long as she would eat out of the feeder ok and drink out of the waterer ok I wasn't too worried about her. She lived to be an old lady.
