Musnad Ahmad 446:1

Musa ibn Dawud narrated to us, he said: Ibn Lahi'ah narrated to us, from Yazid ibn Abi Habib, from Muhammad ibn Yazid, that Abdullah ibn 'Awf narrated to him that Abu Jum'ah Habib ibn Siba'—and he had met the Prophet, may Allah bless him and grant him peace—that the Prophet, may Allah bless him and grant him peace, prayed Maghrib during the Year of the Confederates (al-Ahzab). When he finished, he said: "Has anyone among you known that I prayed Asr?" They said: "O Messenger of Allah, you did not pray it." So he commanded the mu'adhdhin, and he performed the iqamah for the prayer, and he prayed Asr, then he repeated Maghrib.