The Messenger of Allah (ﷺ) said four rak'ahs in the noon prayer while at Medina, but he offered two rak'ahs in the afternoon prayer at Dhu'l-Hulaifa.
Sahih Muslim Book 6, Hadith 12
← Previous Hadith I fell ill and lbn 'Umar came to inquire after my health, and I asked him about the glorification of Allah (i. e. prayer) while travelling. Thereupon he said: I accompanied the Messenger of Allah (ﷺ) on a journey but I did not see him glorifying Him, and were I to glorify (Him). I would have completed the prayer. Allah, the Exalted, has said:" Verily there is a model pattern for you in the Messenger of Allah."

Sahih Muslim Book 6, Hadith 11 Next Hadith → I observed four rak'ahs in the noon prayer with the Messenger of Allah (ﷺ) at Medina, and said two rak'ahs in the afternoon prayer at Dhu'l-Hulaifa.

Sahih Muslim Book 6, Hadith 13