Middle Part Of My Hair Won’T Hold Colour !!

hi !! in june ish, i bleached my hair a couple times (hated it haha) and then dyed it to brown. the brown then grew out over a couple months until my roots were a few inches. i dyed my hair red and it faded almost instantly, but my roots and the ends of my hair were fine. i dyed it again, and while the colour is better, the subsection of my hair still faded to a brown instantly - it just won’t hold colour ?!??? so my roots and ends are bright red with a brown middle section haha. …