Anas bin Malik (RA) reported: The Messenger of Allah (ﷺ) observed Qunut for a month in the dawn prayer after ruku' and invoked curse upon Ri'l, Dhakwan, and said that 'Usayya had disobeyed Allah and His Apostle (ﷺ) .
Hadith ReferenceSahih Muslim / The Book of Mosques and Places of Prayer / Hadith: 677