Answer:
(Fatwa: 392/392=M/1429)
If someone recalls after completion of his salah that he left a rukn (obligatory part) of the salah then he has to perform the salah again; it is not sufficient to do sajda sahv.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband
