They committed zina then got married, and they cannot remember if they repented before doing the marriage contract or not; do they have to do a new marriage contract?

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Check below answers in case you are looking for other related questions:
If a woman commits zina, then she is forced to marry a chaste man, is that marriage valid?
He committed zina with a woman when she was menstruating; does he have to offer the expiation for having intercourse during menses?

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Related Answers:
Is it permissible for one who has committed zina (fornication or adultery) to get married after he or she has repented?
It is not permissible to marry a zaani or zaaniyah unless they have repented
Her father engaged her to him, then her father died and her paternal uncles want to change the agreement
If a woman commits zina, then she is forced to marry a chaste man, is that marriage valid?
He committed zina with a woman when she was menstruating; does he have to offer the expiation for having intercourse during menses?

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