Can the Mahdi's name be other than "Muhammad" or "Ahmad," and can his father's name be other than the Prophet's father's name (peace be upon him), and is there an authentic hadith stating that the Mahdi's name is "Muhammad ibn Abdullah"?

The Mahdi, who will be sent at the end of time, his name will match the name of the Prophet, peace and blessings be upon him, and his father's name will match his father's name, meaning: "Muhammad ibn Abdullah." Scholars such as Sheikh al-Islam Ibn Taymiyyah, Ibn Kathir, and al-Qari have explicitly stated this. The hadith indicates that the intended name is the Prophet's most famous name, "Muhammad," and that the father's name refers to the immediate father, not one of the grandfathers, in order to specify the Mahdi's name and avoid confusion. As for the other names like al-Mahi (the Effacer), al-Hashir (the Gatherer), and al-Aqib (the Successor), they require explanation of their meaning and clarification of the attribute they entail.