The Prophet ﷺ forbade a man to pray with his hair tied up in a knot.
حدثنا عبد الرزاق حدثنا سفيان عن مخول عن رجل
نهى النبي ﷺ أن يصلي الرجل ورأسه معقوص
Its isnad is daif, due to the anonymity of the narrator from Abu Rafi. As for Makhwal, he is Ibn Rashid, and he is trustworthy, his hadith is found among the group [of hadith compilers]. The hadith was narrated by Abu Dawud 1/174 no. 646, Tirmidhi 2/223 no. 384, who graded it hasan, Ibn Majah 1/331 no. 1042, and Bayhaqi 2/109, all of them in the chapter on prayer, and likewise Ibn Khuzayma 2/58 no. 911.