Sunan an-Nasa'i 1256
It was narrated that Ibrahim bin Suwaid said:
"Alqamah prayed five (rak'ahs) and was told about that. He said: 'Did I really do that?' I nodded yes. He said: 'What about you, O odd-eyed one?' I said: 'Yes'. So he prostrated twice, then he narrated to us from 'Abdullah that the Prophet (ﷺ) prayed five (rak'ahs), and the people whispered to one another, then they said to him: 'Has something been added the prayer?' He said: 'No.' So they told him, and he turned around and prostrated twice, then he said: 'I am only human; I forget as you forget.'"
أَخْبَرَنَا مُحَمَّدُ بْنُ رَافِعٍ، قَالَ حَدَّثَنِي يَحْيَى بْنُ آدَمَ، قَالَ حَدَّثَنَا مُفَضَّلُ بْنُ مُهَلْهَلٍ، عَنِ الْحَسَنِ بْنِ عُبَيْدِ اللَّهِ، عَنْ إِبْرَاهِيمَ بْنِ سُوَيْدٍ، قَالَ صَلَّى عَلْقَمَةُ خَمْسًا فَقِيلَ لَهُ فَقَالَ مَا فَعَلْتُ ‏.‏ قُلْتُ بِرَأْسِي بَلَى ‏.‏ قَالَ وَأَنْتَ يَا أَعْوَرُ فَقُلْتُ نَعَمْ ‏.‏ فَسَجَدَ سَجْدَتَيْنِ ثُمَّ حَدَّثَنَا عَنْ عَبْدِ اللَّهِ عَنِ النَّبِيِّ صلى الله عليه وسلم أَنَّهُ صَلَّى خَمْسًا فَوَشْوَشَ الْقَوْمُ بَعْضُهُمْ إِلَى بَعْضٍ فَقَالُوا لَهُ أَزِيدَ فِي الصَّلاَةِ قَالَ ‏"‏ لاَ ‏"‏ ‏.‏ فَأَخْبَرُوهُ فَثَنَى رِجْلَهُ فَسَجَدَ سَجْدَتَيْنِ ثُمَّ قَالَ ‏"‏ إِنَّمَا أَنَا بَشَرٌ أَنْسَى كَمَا تَنْسَوْنَ ‏"‏ ‏.‏