A man came to the Prophet ﷺ and asked him about the time of the dawn prayer. When the next morning came, he ordered the prayer to be called as soon as dawn broke, and he led us in prayer. The following day, he waited until it grew light, then ordered the prayer to be called and led us in prayer. Then he said, "Where is the one who asked about the time of prayer? The time is between these two."
أخبرنا علي بن حجر قال حدثنا إسمعيل قال حدثنا حميد
أن رجلا أتى النبي ﷺ فسأله عن وقت صلاة الغداة فلما أصبحنا من الغد أمر حين انشق الفجر أن تقام الصلاة فصلى بنا فلما كان من الغد أسفر ثم أمر فأقيمت الصلاة فصلى بنا ثم قال أين السائل عن وقت الصلاة ما بين هذين وقت
[Sahih] Reported by Ahmad, 3/113, from the hadith of Ismail bin Ulaya, from Humayd Tawil, through his chain of transmission. Yahya Qattan (Ahmad, 1823) and Muhammad bin Abdullah (also, 3/189) also narrated it from Humayd, through his chain of transmission. This hadith has many corroborating narrations.Ismail here refers to Ibn Jafar in this chain of transmission. This hadith is found in Kubra of Nasai, hadith no. 1526.