Abdullah b. Malik ibn Buhaina al-Asadi reported:The Messenger of Allah (ﷺ) stood up (at the end of two rak'ahs) when he had to sit and proceeded on with the prayer. But when he was at the end of the prayer, he performed a prostration before the salutation and then pronounced the salutation
Abu Sa'id al-Khudri reported:The Messenger of Allah (ﷺ) said: When any one of you is in doubt about his prayer and he does Dot know how much he has prayed, three or four (rak'ahs). he should cast aside his doubt and base his prayer on what he is sure of. then perform two prostrations before giving salutations. If he has prayed five rak'ahs, they will make his prayer an even number for him, and if he has prayed exactly four, they will be humiliation for the devil
This hadith has been narrated by Zaid b. Aslam with the same chain of transmitters and he said:He should perform two prostrations before the salutation, as it was mentioned by Sulaiman b. Bilal
Alqama narrated It on the authority of 'Abdullah (b. Mas'ud) who said:The Messenger of Allah (ﷺ) said the prayer; (the narrator added): He made some act of omission or commission when he pronounced salutation; it was said to him: Messenger of Allah, is there something new about the prayer? He (the Holy Prophet) said: What is it? They said: You said prayer in such and such away. He (the narrator) said: He (the Holy Prophet) turned his feet and faced the Qibla and performed two prostrations and then pronounced salutations, and then turned his face towards us and said: If there is anything new about prayer (new command from the Lord) I informed you of that. But I am a human being and I forget as you for. get, so when I forget, remind me, and when any one of you is in doubt about his prayer. he should aim at what Is correct. and complete his prayer in that respect and then make two prostrations