The imam’s sajda al-sahw in a four-rak‘a prayer

Question

In a four-rak‘a prayer sajda al-sahw became due upon the imam. After praying two rak‘as the imam gave the salam for sajda al-sahw, then remembered that it was a four-rak‘a prayer and prayed two more rak‘as. Does that same sajda suffice, or will he have to perform another?

Answer

At the end of the prayer he should perform sajda al-sahw again.

Source: Fatawa Mahmudiyya

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