Nazir 4:2

Let’s say that a man says that he is a nazir and then asks his wife, “What about you?” If she replies “Amen,” he can annul her vow and his still stands. Let’s say the wife says that she is a nazir and asks her husband, “What about you?” If he replies “Amen,” he cannot annul her vow (because he has already confirmed it).

Nazir 4:3

If a woman accepted nezirus and then intentionally drank wine or became impure for a corpse (willfully violating the Torah prohibition), she receives 40 lashes (as is normally the case). If her husband annulled her obligation to observe nezirus but she didn’t know it and she drank wine or became impure for a corpse, she does not receive 40 lashes. Rabbi Yehuda says that she may not receive lashes but she does receive the stripes administered for acting rebelliously.