This was narrated by Ahmad ibn Muhammad ibn Isa from Ali ibn al-Hakam from Sulaym al-Farra, who said: I asked Imam عليه السلام about a man who is the mu’adhdhin for a group and their imam (of prayer) is (away) on the road to Mecca or elsewhere, so he leads them in Asr prayer at its proper time. Then a man enters who does not know (the situation) and assumes that it is Dhuhr, does it suffice him that it was actually Asr? Imam عليه السلام said: “No.”