—the first is vocalised with fatḥa, while this one is with ḍamma.
I say: al-Ṣūrī’s statement that there are two only holds if we limit ourselves to the two names already mentioned; once we take into account the additional individual cited by al-Dāraqutnī, they would number three.
Al-Dāraqutnī said: “Muḥammad ibn Ḥubban ibn Bakr ibn ʿAmr al-Baṣrī settled in Baghdad, in the district of al-Mukharrim. He narrated from Umayya ibn Bisṭām, Muḥammad ibn Minhal, and others.”
I say: The apparent conclusion—just as we have noted—is that they are in fact one person. What leaves me with no doubt is that the Muḥammad ibn Ḥubban who transmits from Abū ʿĀṣim is a single, long-lived narrator, and his patronymic is pronounced with ḍamma. It is nevertheless possible that his father’s name, Ḥubban, was at times read with ḍamma and at other times with fatḥa; Allah knows best.