How to get rid of a bleach stain out of a cotton sweater
Dye the sweater. Bleach isn't a stain...it removed all the color :(I hate when that happens!
Bleach the rest of the sweater, cause that bleach is not coming out..
Or, you could color the spot in with a permanent marker.
It ain't comin out
Re dye the sweater
just like darkness is the absence of light, a bleach "stain" is not a stain but the absence of dye...your only options are to replace the missing dye or remove the rest of it.