'Aishah (May Allah be pleased with her) reported:
Prior to his demise, the Messenger of Allah (ﷺ) used to supplicate frequently: Subhan Allahi wa bihamdihi; Astaghfirullaha wa atubu ilaihi (Allah is free from imperfection, and I begin with praising Him. I beg forgiveness from Allah and I turn to Him in repentance."[Al-Bukhari and Muslim].
App reference: Book 20, Hadith 9
Arabic/English book reference: Book 20, Hadith 1877