Duwaid bin Nafi' said: " Ibn Shihab informed me, saying: 'Ata bin Yazid narrated to me from Abu Ayyub: That the Prophet (ﷺ) said: 'Witr is a duty, and whoever wants to pray witr with seven (rak'ahs), let him do so; whoever wants to pray witr with five, let him do so, whoever wants to pray witr with three, let him do so; and whoever wants to pray witr with one, let him do so.'"