Yahya b. al-Husain reported on the authority of his grandfather that Allah's Apostle ﷺ invoked blessing on the occasion of the Farewell Pilgrimage three times for those who got their heads shaved and once for those who got their hair clipped. In the narration transmitted by Waki' there is no mention of the Farewell Pilgrimage.
أَنَّهَا سَمِعَتِ النَّبِيَّ ﷺ فِي حَجَّةِ الْوَدَاعِ دَعَا لِلْمُحَلِّقِينَ ثَلاَثًا وَلِلْمُقَصِّرِينَ مَرَّةً وَلَمْ يَقُلْ وَكِيعٌ فِي حَجَّةِ الْوَدَاعِ