Hadith #4646 (Sahih Muslim)
Book: The Book on Government
Narrator(s): Usaid bin Hudair bin Sammak
Grade: Sahih

Will you not appoint me governor as you have appointed so and so? He (the Messenger of Allah) said: You will surely come across preferential treatment after me, so you should be patient until you meet me at the Cistern (Haud-i-Kauthar).

Source: https://parallelquran.com/hadith/sahih-muslim-4646/