'Aishah (May Allah be pleased with her) reported

I asked: "O Messenger of Allah ! If I realize Lailat-ul-Qadr (Night of Decree), what should I supplicate in it?" He (ﷺ) replied, "You should supplicate: Allahumma innaka 'afuwwun, tuhibbul-'afwa, fa'fu 'anni (O Allah, You are Most Forgiving, and You love forgiveness; so forgive me)."

[At-Tirmidhi].