I asked Anas bin Malik, "Did the Prophet ﷺ dye his hair?"He replied, "He had only a few grey hairs."
سألت أنس بن مالك أخضب النبي ﷺ؟ قال: إنه لم ير من الشيب إلا قليلا.
Bukhari narrated it in the book of clothing (5894), and Muslim in the book of virtues (2341:102), both from the hadith of Waheeb bin Khalid, from Ayub, from Muhammad bin Sirin, who mentioned it.