I mixed a color for a client's balayage that went totally green
So this client wanted a cool, ashy blonde, and I used my usual formula with a violet additive to cancel warmth. But her hair had some old box dye underneath I didn't catch at first. When I rinsed it out, the midsection had this weird minty green cast. I mean, it was subtle, but definitely there. I had to do a quick color correction with a direct dye remover and a warm, peachy toner to neutralize it. The whole thing added like an extra hour to my appointment. It taught me to do a better strand test on every single section when there's a history of color, even if the client says it's 'all gone'. Has anyone else had a toner go sideways because of hidden underlying pigment?