I fell ill in Persia and therefore, prayed in a sitting posture, and I asked 'A'isha about it and she said: The Messenger of Allah (ﷺ) prayed for a long time in the night sitting.
Sahih Muslim Book 6, Hadith 131
← Previous Hadith 'A'isha reported that the Messenger of Allah (ﷺ) would pray in the night for a long time, and when he prayed standing be bowed in a standing posture, and when he prayed sitting, he bowed in a sitting posture.

Sahih Muslim Book 6, Hadith 130 Next Hadith → I asked 'A'isha about the prayer of the Messenger of Allah (ﷺ) during the night (i. e. Tahajjud prayer) She replied: He used to pray for a long time standing and for a long time sitting in the night, and when he recited the Qur'an while standing, he would bow himself from the standing position, and when he recited while sitting, he would bow from the sitting position.

Sahih Muslim Book 6, Hadith 132