Почему мой ребенок выгибает шею и открывает рот, но отказывается от груди? Помогите!

Breast feeding mums pls help-
What does it mean when baby extends her neck and opens her mouth as if she’s looking for something to latch onto but when I give her the boob she looks disgusted 🤣🤣
So confused as to why she does this