My rabbit keep biting my fiance but not me

Around three weeks ago my rabbit started biting my fiance when he goes to feed her. It started with it being occasionnel but now it's everyday. She only does it when it's him and when he's giving her her kibble. We're really confuse as to why she's doing this. She's 1,5 years old and we adopted her when she was 2months old. We also havent got her spayed yet.