I saw the Prophet (ﷺ) and saw some white hair below his lower lip above the chin.
Sahih al-Bukhari Book 61, Hadith 54
← Previous Hadith I heard Abii Juhaifa saying, "I saw the Prophet, and Al-Hasan bin `Ali resembled him." I said to Abu- Juhaifa, "Describe him for me." He said, "He was white and his beard was black with some white hair. He promised to give us 13 young she-camels, but he expired before we could get them."

Sahih al-Bukhari Book 61, Hadith 53 Next Hadith → That he asked `Abdullah bin Busr (i.e. the companion of the Prophet), "Did you see the Prophet (ﷺ) when he was old?" He said, "He had a few white hairs between the lower lip and the chin."

Sahih al-Bukhari Book 61, Hadith 55