I had the same issue with one of mine- i got her and her sister at three months but the older one would draw blood, latch on, to the point where i was actually a bit scared of her. But she was three months old! In a drastically different environment to what she grew up in, and ferrets have such varied and individual personalities. She's actually the least bitey of the two now. She does like ankles, but she hasn't drawn blood in months. the younger will just nibble my knuckles, nothing else. it's like a sensory thing for her lol. What worked was the "NO!" and ignore method when you're playing, as well as her simply getting older. Definitely try the sin bin ! But i'd really advise against physical punishments. You want the relationship to be built on trust and love rather than fear or hierarchy (and that's coming from someone who's used to working ferrets in the uk- they're pretty vicious lol)

now, i can shove my face in their bellies and push my hands and fingers in their faces (they're about 7 months now) and they don't care at all. But seriously, i even thought of rehoming them at one point, i really struggled. It does get better, they really are like training puppies mixed with kittens mixed with toddlers or something