Fix Brassy Roots

I had previously colored my hair black from a box color. I tried to color again to a dark brown. My roots turned a light brassy color and the rest of my hair stayed dark. What can I do to make all my hair a dark brown?

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You'll need to apply the dark brown color on your roots with a 10 volume peroxide. When you have red in your hair naturally and try to lift a dark color to a lighter color, roots can turn brassy because the heat from your scalp processes them more and faster.