Is it okay to use medium brown FILLER on blonde highlights to dye BLACK?

Natural hair colour : dark brown


Current hair colour : Dark brown/light brown/ blonde highlights


Desired hair coour : Black





I was told to use a medium brown filler before dying it black, will this work? Or do I need a red filler.


Thanks.Is it okay to use medium brown FILLER on blonde highlights to dye BLACK?
You can just dye it black.Is it okay to use medium brown FILLER on blonde highlights to dye BLACK?
i dont think it will work