Musnad Ahmad 31:478

Hassan ibn Musa narrated to us, Shaiban narrated to us, from Yahya, Iyad ibn Hilal al-Ansari narrated to me, he said: I heard Abu Sa’id al-Khudri saying: The Messenger of Allah (ﷺ) said: "If one of you prays and forgets how much he has prayed—or he said: and he does not know whether he added or subtracted—then let him prostrate two prostrations while he is sitting. And if Satan comes to one of you and says: 'You have broken your ablution,' then let him say: 'You have lied,' unless he heard it with his ear or smelled its odor with his nose."