Repeating one sura in every rak‘a

Question

If in some prayer one forgetfully recited “Qul a‘udhu bi-rabbi al-nas” (قُلْ أَعُوذُ بِرَبِّ ٱلنَّاسِ) already in the first rak‘a, which sura should one then recite in the second, third and fourth?

Answer

He should complete the prayer by reciting this same sura in every rak‘a.

Source: Fatawa Mahmudiyya

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