The Prophet ﷺ said, "I have been commanded." Hammad said, "Your Prophet ﷺ was commanded to prostrate on seven points and not to tuck up his hair or his garment."
حدثنا مسدد وسليمان بن حرب قالا حدثنا حماد بن زيد عن عمرو بن دينار عن طاوس
عن النبي ﷺ قال أمرت قال حماد أمر نبيكم ﷺ أن يسجد على سبعة ولا يكف شعرا ولا ثوبا
Bukhari reported it in the Book of Adhan, Chapter: One should not tuck up one's hair, Hadith: 815, and Muslim, the Book of Prayer, Chapter: The limbs of sujud and the prohibition of tucking up the hair and garment, etc., Hadith: 490, from the hadith of Hammad bin Zayd, through the same chain.