If he remembers a missed prayer during the current prayer or after finishing it

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Check below answers in case you are looking for other related questions:
When he was praying Zuhr, he remembered that he had not prayed Fajr
Praying Maghrib behind one who is praying ‘Isha’

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Related Answers:
She missed some prayers in the past – what should she do?
He prayed for three years without doing ghusl from janaabah
In what order missed prayers should be made up
When he was praying Zuhr, he remembered that he had not prayed Fajr
Praying Maghrib behind one who is praying ‘Isha’

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