"I asked 'Aishah, what was the supplication that the Prophet [SAW] said the most? She said: 'The supplication that he said the most was: Allahumma, inni a'udhu bika min sharri ma 'amiltu wa min sharri ma lam a'mal ba'd (O Allah, I seek refuge with You from the evil of what I have done, and from the evil of what I have not done yet.)'" (Using translation from Nasāʾī 5524)
سُئِلَتْ عَائِشَةُ مَا كَانَ أَكْثَرَ مَا كَانَ يَدْعُو بِهِ النَّبِيُّ ﷺ؟ فَقَالَتْ كَانَ أَكْثَرَ دُعَائِهِ أَنْ يَقُولُ «اللهُمَّ إِنِّي أَعُوذُ بِكَ مِنْ شَرِّ مَا عَمِلْتُ وَمِنْ شَرِّ مَا لَمْ أَعْمَلْ بَعْدُ»