The ruling on one who conditions his vow on something that occurs but he does not fulfill his vow

السؤال:
In the second question from Umm 'Umar from Bahrain, she says, "Your Eminence, I have a friend who made a vow when she was in school that if she passed, she would fast for a full month. When the results were announced, she was surprised to find her name among those who failed. Upon reviewing the names, it turned out she had passed and was among the successful, but she did not fast. It has now been about nine years. Should she fast with an expiation?"

Answer:
She must fast; because the Messenger (peace and blessings be upon him) said: This is a hadith that came from the Messenger of Allah (peace and blessings be upon him): And since she vowed if she passed, and it has become clear that she passed, she must fast what she vowed. It is sufficient if she fasts it, and praise be to Allah, even if it is delayed. As soon as she learns of it, she must hasten and be prompt, and praise be to Allah.

The presenter: Praise be to Allah. May Allah reward you.