The Messenger of Allah ﷺ said, "Allah has those whom He frees from the Fire every day and every night, and each one of them has a supplication that will be answered."
قال رسول الله ﷺ: إن الله عتقاء في كل يوم وليلة، لكل عبد منهم دعوة مستجابة.
Ahmad (7450) narrated it from Abu Muawiya, who said, Amash narrated to us, from Abu Salih, from Abu Hurairah or Abu Saeed, and he mentioned it. The uncertainty comes from Amash, and uncertainty in identifying the companion does no harm. This unrestricted wording came restricted to the month of Ramadan, as in the hadith that follows.