Hello :) I dyed my hair blue with Directions Midnight Blue (december 2017). It faded to a turquoise. I tried dyeing it brown by using copper-red hair dye and brown hair dye on top of it but it left some little green stains. It's been almost half of a year and I would like to dye my hair again. If I bleach it, will there still be green stains?
There might be. I suggest that, if there are green stains when you lighten, to tone it with pink eye diluted with conditioner until it is a pale pink. That should neutralize the color.
Before you do that, though, I advise removing the colors on your head with some Joico color remover or a bleach bath first. Using straight bleach right away may result in driving the color further into the cuticle, causing more stains on the hair.