بسم الله الرحمن الرحيم
(1-6) It is allowed to dye the hair other than the black dye provided after applying the dye it does not leave layer like paint on the hair. However, you may use other colour of henna instead of black. It is sunnah to use red henna. Black henna is unlawful as Hadith warns those who apply it. It is recorded in Hadith: “There will be people in latter ages who will dye their hair like craws of pigeons, they will not smell even the fragrance of the Paradise.”
Allah knows Best!
Darul Uloom Deoband
This answer was collected from the official ifta website of Darul Uloom Deoband in India.