Abu Musa al-Ash'ari (RAA) narrated, "The Messenger of Allah (ﷺ) used to supplicate, "O Allah, forgive me my faults, my ignorance, my immoderation in my concern. And you are better aware (of my affairs) than myself. O Allah, grant me forgiveness (of the faults which I committed) seriously or otherwise (and which I committed) inadvertently and deliberately. All these (failings) are in me. O Allah, grant me forgiveness from the faults, which I did in haste or deferred, which I committed in privacy or in public and you are better aware (of them) than myself. You are the First and the Last and over all things you are Omnipotent." Agreed Upon.
English reference: Book 16, Hadith 1606
Arabic reference: Book 16, Hadith 1563