How do i make the dark hair dye stay and not fade?

my hair is naturally light brown , and i once dyed it auburn and now whenever i try and dye my hair dark red or dark brown, the hair color fades and turns back into auburn. even if my roots are half grown out and i dye my hair, everything goes back to auburn, even my roots. how do i prevent this, and how can i make the dark hair dye stay without fading?

How do i make the dark hair dye stay and not fade?

wash in cold water with a very mild shampoo

stay out of the sun

wear a hat