All praise is due to Allah, peace and blessings be upon Prophet Mohammad and upon all of his family and righteous companions.
Among the Sharee`ah conditions for Zakaah (obligatory charity) - once it reached Nissab(Minimum amount liable for Zakaah) and a lunar year lapsed on it- is that it should be given for the eight Zakaah disbursement channels, which Allah, The Exalted, had clarified in the following verse: “Alms are for the poor and the needy, and those employed to administer the (funds); for those whose hearts have been (recently) reconciled (to Truth); for those in bondage and in debt; in the cause of God; and for the wayfarer: (thus is it) ordained by God, and God is full of knowledge and wisdom. “ {At-Tawbah/60}. If it wasn`t given to any of the above, such as giving it to a rich person supposing that he is poor, then it doesn't avail the giver; rather, it is imperative that he repays it to its eligible recipients.
As regards the giver`s right in claiming what he had given, there are two situations: First: If the giver told the recipient that it is the Zakaah of his money, then he has the right to claim it if it wasn`t spent, or take an equal amount if it was. However, if he didn`t manage to take it back, then he is obliged to pay the Zakaah once more. Second: If the giver didn`t tell the recipient that it is the Zakaah of his money, then he has no right to claim it since in this case it becomes a gift, or a charity that has been received by the rich and thus it is impermissible for the giver to take it back.
It is incumbent upon the giver of the Zakaah to be on the safe side, and make sure that the Zakaah is delivered to its eligible recipients. Therefore, it is impermissible for him to pay it, except to those whom he is sure that they are entitled to receive it.