It was written in her marriage contract that she had received her mahr but she has not received it and she has started to resent her husband

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Check below answers in case you are looking for other related questions:
The mahr (dowry) is the right of the wife
Ruling on including a list of furniture in the mahr

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Related Answers:
He wrote a list of furnishings for her on condition that she lives with him without causing problems for one year
He divorced her in return for half of the mahr after he accused her. Does he have the right to this money?
A Christian woman has the right to ask for a dowry from her Muslim husband
The mahr (dowry) is the right of the wife
Ruling on including a list of furniture in the mahr

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