"The Prophet (S) prayed five (Rakah) for Zuhr, so it was said to him: 'Has the prayer been added to, or have you merely forgotten?' So he (S) performed two prostrations after he had said the Salam." (Using translation from Tirmidhī 392)
صَلَّى نَبِيُّ اللهِ ﷺ الظُّهْرَ خَمْسًا فَقَالُوا أَزِيدَ فِي الصَّلَاةِ؟ فَسَجَدَ سَجْدَتَيْنِ