Returning to Natural Hair Color After Dyeing?

My hair was black brown and then one summer I asked my mom to give me highlights. They didn't turn out how I wanted them to so I dyed it black. It left some brown (from the highlights) so I just recently, yesterday, dyed it again. I asked my mom for black, but she got dark brown. So I dyed it once again and now the roots and a bit lower are brown (super noticeable) and the rest of the hair is dark brown. I hate it, I just want my original hair color back! What do I do?