He fell behind during the last ten [nights], so he prayed in his house, and they used to say: "Ubayy has run away."(1)

Abu Dawud said: This indicates that what was mentioned regarding the qunut is nothing, and these two hadiths indicate the weakness of the hadith of Ubayy that the Prophet, peace and blessings be upon him, performed qunut in the Witr.

‌‌339 - Chapter: Supplication after the Witr

1430 - 'Uthman ibn Abi Shaybah narrated to us, Muhammad ibn Abi 'Ubaydah narrated to us, my father narrated to us, from al-A'mash, from Talhah al-Iyami, from Dharr, from Sa'id ibn 'Abd al-Rahman ibn Abza, from his father, from Ubayy ibn Ka'b, who said: When the Messenger of Allah, peace and blessings be upon him, gave the salutation in the Witr, he would say: "Glory be to the King, the Holy."(2)

--------------------------------------------
(1) Authentic apart from the mention of restricting it to twenty nights then Ubayy falling behind in the last ten, and this chain is weak due to its discontinuity, for al-Hasan—namely al-Basri—did not meet 'Umar ibn al-Khattab, as al-Hafiz al-Mundhiri indicated in "Mukhtasar al-Sunan."
Al-Bayhaqi also recorded it in 2/498 via the path of Abu Dawud, with this chain.
Ibn Abi Shaybah recorded it in 2/305 via the path of Qatadah from al-Hasan, similar to it.
However, the mention of qunut in it during the latter half has been authenticated from the hadith of 'Urwah ibn al-Zubayr, from 'Abd al-Rahman ibn 'Abd al-Qari, and we have cited it with the preceding hadith.

(2) Its chain is authentic. Abu 'Ubaydah: he is 'Abd al-Malik ibn Ma'n al-Hudhali, and al-A'mash: he is Sulayman ibn Mihran, and Talhah al-Iyami: he is Talhah ibn Musarrif al-Yami, and Dharr: he is Ibn 'Abd Allah ibn Zurarah.
Al-Nasa'i also recorded it in "al-Kubra" (446), (1433), (1436), (10497), (10502), and (10508) via multiple paths from Sa'id ibn 'Abd al-Rahman, with this chain.
Al-Nasa'i also recorded it in (447), (1438), (1439), (1450), (1452), (10498), (10499), (10501), (10503–10507), and (10509–10511) via multiple paths from =