Ruling on adding a surah after al-Fatihah in the last two rak'ahs of the four-rak'ah prayer

The questioner: This is the imam of a mosque, and one of the ma'mum (those praying behind him) objected to him, saying: You are reciting a surah after al-Fatihah in the last two rak'ahs of the Zuhr and 'Asr prayers.And he said: He asked some of the shaykhs, and they said: This is contrary to the Sunnah. Is this correct?The Shaykh: The scholars (may Allah have mercy on them) differed on this issue: whether one should recite in the last two rak'ahs of Zuhr and 'Asr or not. The well-known position in the madhhab of Imam Ahmad is that one does not recite, but restricts oneself to al-Fatihah only, based on what is established in the two Sahihs from the hadith of Abu Qatadah (may Allah be pleased with him) (that the Prophet (peace and blessings be upon him) used to recite in the last two rak'ahs only al-Fatihah)And some said: There is no harm in reciting, because of the hadith of Abu Sa'id al-Khudri (may Allah be pleased with him), who said: (We estimated the standing of the Messenger of Allah (peace and blessings be upon him) in prayer, and it is mentioned in a way that indicates he recited in the last two rak'ahs) But this hadith is unique to Muslim, while the first one is in the two Sahihs. So some of them preferred the first one and said: This is anomalous (shadhdh).And he also said: The hadith of Abu Qatadah is explicit that he recited or did not recite.And this one says: "We estimated," and "estimation" means approximation and guessing, and approximation and guessing are not like certainty. What appears is that there is no harm in doing it occasionally, but as for making it a constant habit, that is not allowed.