Sahih muslim:1306d Chapter: What one who has entered Ihram for Hajj or Umrah is permitted to wear, and what is not permissible, and perfume is forbidden for him Book 15, Hadith 363

Abdullah b. Amr b. al-‘As (Allah be pleased with them) reported: As Allah’s Apostle. (ﷺ) was delivering sermon on the Day of Nahr, a man stood up before him and said: Messenger of Allah, I did not know that such and such (rite was to be performed) before such and such (rite). Then another man came and said: Messenger of Allah, I thought that such and such (rite) should precede such and such (rite), and then another man came and said: Messenger of Allah, I had thought that such and such was before such and such, and such and such (is the sequence) of the three (rites, viz. throwing of pebbles, sacrificing of animal and shaving of one’s head). He said to all these three: Do now (if you have not observed the cequence) ; there is no harm in it.