If you’ve tried everything and still have a hint of purple, don’t despair. There are actual color-removing products out there, like the ones from Malibu C or even a gentle dandruff shampoo (yes, it’s clarifying enough to strip dye). Apply, leave on for 5 minutes, and rinse.
You can also do a baking soda paste—mix two tablespoons of baking soda with enough water to make a paste. Massage it into your hair, let it sit for a few minutes, and rinse. This is a lightweight abrasive that lifts color without the harshness of dish soap. Use it sparingly; baking soda can be drying.
And if you’re still stuck? Go to a salon and ask for a clarifying treatment. A professional can fix this in minutes, and they’ve seen way worse than your Smurf-ish locks. I once saw a woman with hair so purple it looked bathed in grape juice—they fixed it before she could finish her latte.