My answer might be a bit controversial so maybe use this as a last resort but, I used to use Splat back as a teen... most say NOT to use it because they claim it NEVER leaves your hair, but it wasn't true for me when i used their pink dye, it washed out within a month or so. But if you want something permanent, apparently Splat is a good bet for that..?? it's got a fuckton of chemicals tho and people compare it to fabric dye so keep that in mind. But it never caused any weird reactions for me and I have super sensitive skin. I don't see anyone saying it caused any hair damage, the only complaints i see are about how tough it is to remove.