What is the ruling on calling one's maternal uncle "Abd al-Nabi" and is the person who named him that sinful?

Many scholars have agreed on the prohibition of naming with any name that implies servitude to other than Allah, such as "Abd al-Nabi" (slave of the Prophet), "Abd al-Masih" (slave of the Messiah), and "Abd al-Kaaba" (slave of the Kaaba). Whoever was named with such a name must change it to a name acceptable by Islamic law. It is forbidden to call him by the first name, and whoever does so is sinful. The grandparents who gave him this name are considered sinful if they knew of the prohibition of this type of naming. However, if they did so out of ignorance, we hope that they bear no sin, for Allah Almighty says: "And there is no blame upon you for that in which you have erred, but [only for] what your hearts intended. And ever is Allah Forgiving and Merciful." (Al-Ahzab:5).