“The Messenger of Allah ﷺ offered prayer, and I am not sure whether he did something extra or omitted something. He asked, and we told him, so he turned to face the Qiblah and prostrated twice, then he said the Salam. Then he turned to face us and said: ‘If any new command has been revealed concerning the prayer, I would certainly have told you. But I am only human and I forget and you forget. If I forget, then remind me. And if anyone of you is uncertain about the prayer, let him do what is closest to what is correct, then complete the prayer, say the Salam and prostrate twice.” (Using translation from Ibn Mājah 1211)
صَلَّى رَسُولُ اللهِ ﷺ صَلَاةً لَا أَدْرِي زَادَ أَمْ نَقَصَ إِبْرَاهِيمُ الْقَائِلُ لَا يَدْرِي عَلْقَمَةُ قَالَ زَادَ أَوْ نَقَصَ أَوْ عَبْدُ اللهِ ثُمَّ اسْتَقْبَلَنَا فَحَدَّثْنَاهُ بِصَنِيعِهِ فَثَنَى رِجْلَهُ وَاسْتَقْبَلَ الْقِبْلَةَ وَسَجَدَ سَجْدَتَيْنِ ثُمَّ أَقْبَلَ عَلَيْنَا بِوَجْهِهِ فَقَالَ لَوْ حَدَثَ فِي الصَّلَاةِ شَيْءٌ لَأَنْبَأْتُكُمُوهُ وَلَكِنْ إِنَّمَا أَنَا بَشَرٌ أَنْسَى كَمَا تَنْسَوْنَ فَإِنْ نَسِيتُ فَذَكِّرُونِي وَأَيُّكُمْ مَا شَكَّ فِي صَلَاتِهِ فَلْيَتَحَرَّ أَقْرَبَ ذَلِكَ لِلصَّوَابِ فَلْيُتِمَّ عَلَيْهِ وَيُسَلِّمْ ثُمَّ يَسْجُدْ سَجْدَتَيْنِ