Sunan Ibn Majah
1205
Sahih+3

It was narrated that ‘Abdullah said:“(Once) the Prophet (ﷺ) prayed Zuhr with five Rak’ah, and it was said to him: ‘Has something been added to the prayer?’ He said: ‘What is that?’ They told him, and he turned back towards the Qiblah and performed two prostrations.”

SahihAl-Albani
SahihMuhammad Fouad Abd al-Baqi