Giving Zakat to the non-Muslim poor.
Some people give Zakat to the non-Muslim poor and think that their Zakat has been paid, whereas in this case, the Zakat has not been paid, because the recipients of Zakat are only the Muslim poor; therefore, it is obligatory upon them to give the same amount of Zakat again to poor Muslims. (Aham Masail/Vol:3/Page:135)