She vowed to fast for a month if Allaah caused her husband to mend his ways

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Check below answers in case you are looking for other related questions:
A vow to do something that Allah has made obligatory and enjoined upon people is not valid
She made a vow and does not remember if she intended it to be ongoing or to be done only once

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Related Answers:
Punishment for not fulfilling vows
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She swore that she would not speak to her and she sent her a text message; has she broken her oath?
A vow to do something that Allah has made obligatory and enjoined upon people is not valid
She made a vow and does not remember if she intended it to be ongoing or to be done only once

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