Umm al-Mu'minin, the mother of the believers `Aisha [may Allah be pleased with her] was asked what the Prophet Muhammad ﷺ supplicated during the last ten days of Ramadan.
اللَّهُمَّ إِنَّكَ عَفُوٌ تُحِبُّ الْعَفْوَ فَاعْفُ عَنِّي
Allahumma innaka `Afuwwun TuHibbul `Afwa Fa`fu `Annii.
'O Allah, you are the Forgiver, You love to forgive, so forgive me.'
- Musnad Ahmad, Sunan ibn Majah and at-Tirmidhi.
Make this du`a as much as you can. Call on Allah for there is no Helper but He.