Is it permissible to wash and comb hair during the state of Ihram for cleanliness, knowing that some of his hair falls out during washing, and is it permissible to comb hair during the state of Ihram?

There is no harm for a pilgrim in the state of ihram to wash their head or body with something that contains no perfume. However, they should not do anything that causes their living hair to fall out, such as rubbing vigorously or combing. If dead hair falls out, there is no penalty. But if it is certain that the fallen hair is alive, then a fidyah (expiatory payment) is due.