Vowing to give away one third of his money during Ramadan but forgetting

Q: If someone paid the Zakah (obligatory charity) due on their wealth at a specific time and then another Hawl (one lunar year calculated from the time a property reaches the minimum amount upon which Zakah is due) passed, but they forgot the date of the next Hawl, what is the Kaffarah (expiation) for this? May Allah reward you with the best!Also, if someone vowed to give one-third of their wealth away as Sadaqah (voluntary charity) in Ramadan, but when the month came, they forgot their vow, should they offer Kaffarah or what else should they do? Please give us a Fatwa (legal opinion given by a qualified Muslim scholar) on this and may Allah bless you for it!

A: The person has to fulfill their vow by giving one-third of their wealth away as Sadaqah when they remember their oath and they have to pay the Zakah when they think it most likely that the Hawl has fully passed.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.