Must what was deficient in Zakat from previous years be paid after the deficiency is discovered?

You must immediately disburse the remaining Zakat; it is an obligatory right for the eight categories mentioned by Allah Almighty in Surat At-Tawbah: the poor, the needy, those employed to collect it, those whose hearts are to be reconciled, for freeing captives, those in debt, in the cause of Allah, and the wayfarer. It must be disbursed to them, no matter how long the delay has been.