Ruling on a pilgrim in the state of ihram shortening his own hair and the hair of others

Some people say, at the place of sa'y and when shortening the hair: It is not permissible for a man in the state of ihram to cut his own hair; rather, it is obligatory that someone else cut it for him. What is the correctness of this statement?
Answer: There is no harm if he cuts his own hair; there is no harm. Or if he shortens the hair of his brother who is in the state of ihram, likewise, even if he has not exited the state of ihram; because it is something permitted. So if he shortens his own hair while in the state of ihram... in Hajj and 'Umrah, or if he shortens the hair of his brothers as long as they have performed tawaf and sa'y in 'Umrah, and even if he himself has not shortened his hair, there is no blame on him; because he performed a prescribed act. Yes.
The presenter: May Allah reward you with good.