The Prophet (ﷺ) said "The most superior way of asking for forgiveness from Allah is: 'Allahumma anta Rabbi la ilaha illa anta, Khalaqtani wa ana `Abduka, wa ana `ala `ahdika wa wa`dika mastata`tu, A`udhu bika min Sharri ma sana`tu, abu'u Laka bini`matika `alaiya, wa abu'u laka bidhanbi faghfir lee fa innahu la yaghfiru adhdhunuba illa anta." The Prophet (ﷺ) added. "If somebody recites it during the day with firm faith in it, and dies on the same day before the evening, he will be from the people of Paradise; and if somebody recites it at night with firm faith in it, and dies before the morning, he will be from the people of Paradise."
Sahih al-Bukhari Book 80, Hadith 3
← Previous Hadith that the Prophet (ﷺ) said, "For every prophet there is an invocation that surely will be responded by Allah," (or said), "For every prophet there was an invocation with which he appealed to Allah, and his invocation was accepted (in his lifetime), but I kept my (this special) invocation to intercede for my followers on the Day of Resurrection."

Sahih al-Bukhari Book 80, Hadith 2 Next Hadith → I heard Allah's Messenger (ﷺ) saying." By Allah! I ask for forgiveness from Allah and turn to Him in repentance more than seventy times a day."

Sahih al-Bukhari Book 80, Hadith 4