Sunan Abi Dawud 1022

‘Abd Allah (b. Mas’ud) said; The Messenger of Allah (ﷺ) led us in five rak’ahs of prayer. When he turned away (i,e, finished his prayer), the people whispered among themselves. He asked; what is the matter with you ? They said :Messenger of Allah, has (the number of the rak’ahs of) the prayer been increased ? he said : No. they said; you have offered five rak’ahs of prayer. He then turned away and performed two prostrations, and afterwards gave the salutation. He then said : I am only a human being, I forget, as you forget