Sunan Ibn Majah 1211

Muhammad bin Bashshar narrated to us: Muhammad bin Jafar narrated to us: Shubah narrated to us, from Mansur. Shubah wrote to me, and I read it to him. He said: Ibrahim informed me, from Alqamah, from Abdullah, who said: The Messenger of Allah (ﷺ) prayed a prayer without knowing whether he had added or omitted something. He asked, and we told him. So he drew in his leg, faced the qiblah, and performed two prostrations, then gave the taslim. Then he turned toward us and said: If anything had happened in the prayer, I would have informed you. I am only a human being; I forget just as you forget. When I forget, remind me. If any of you is uncertain in prayer, let him seek out what is closest to what is correct, complete the prayer on that basis, give the taslim, and perform two prostrations.