اللهم اغفر لي خطيئتي وجهلي، وإسرافي في أمري، وما أنت أعلم به مني، اللهم اغفر لي جدي وهزلي، وخطئي وعمدي، وكل ذلك عندي
Allahumm-aghfir li khati'ati, wajahli, wa israfi fi amri, wa ma Anta a'lamu bihi minni. Allahumm-aghfir li jiddi wa hazli, wa khata'i wa 'amdi, wa kullu dhalika 'indi.
O Allah! Forgive my errors, ignorance and immoderation in my affairs. You are better aware of my faults than myself. O Allah! Forgive my faults which I committed in seriousness or in fun deliberately or inadvertently.
[Al-Bukhari and Muslim].

Laylatul Qadr Dua will Forgive All Your Sins and past Mistakes - BEST FORGIVNESS DUA RECITED BY SAAD AL QURESHI