Sa‘d ibn Abdullah, from Abu Ja‘far, from Ali ibn al-Hakam, from Aban ibn Uthman, from Mansur ibn Hazim, from Abu Abdillah عليه السلام, peace be upon him, who said: I asked Him عليه السلام about a man who prayed and then remembered that he had added an extra prostration. Imam عليه السلام said: "He does not repeat the prayer because of a (mistaken) prostration, but he does repeat it because of a (mistaken) rak‘ah."