Hadith #1060 (Sunan Ibn Majah)
Book: Establishing the Prayer and the Sunnah Regarding Them
Narrator(s): al-Lyth bin Abi Sulaym الليث بن أبي سليم, ibn Umar, Ishaq bin 'Uthman al-Klaby إسحاق بن عثمان الكلابي, Nafie' نافع مولى ابن عمر, Ubaidullah bin 'Amr bin Abi Walid عبيد الله بن عمرو بن أبي الوليد

“The Messenger of Allah (ﷺ) said: ‘Whoever fasts Ramadan and spends its nights in prayer, out of faith and in hope of reward, his previous sins will be forgiven.’”

Source: https://parallelquran.com/hadith/sunan-ibn-majah-1060/