Sunan an-Nasa'i 1241

Muhammad ibn ‘Abd Allah ibn al-Mubarak al-Mukharrami reported to us; he said: Waki‘ reported to us, from Mis‘ar, from Mansur, from Ibrahim, from ‘Alqamah, from ‘Abd Allah, who said: The Messenger of Allah (ﷺ) said: “If any one of you is uncertain about his prayer, let him seek what he believes to be correct and prostrate twice after he has finished.”