Light Brown Hair Color

I want to die my hair back to its original color (dark brown, almost black), but I've dyed my hair so many times and now its a light brown with my roots showing. im afraid that if I dye it dark brown, the roots will look darker and the bottom will look lighter .. What should I do ... should I dye it dark brown, black .. I just want it to look the same ...

If you choose a dark color must match, but the hair that is closest to the scalp absorb the color more quickly because of body heat.
Otherwise, go to a salon:)