henna product not the color on box

[sunny-dew]

The product said ash brown but it made my hair a red color. I would like to get a refund, but seller has closed my request. I have bought Henna before that gave me exactly an ash brown color so I know it's possible. I think the label on the box as ash brown should be noted, that it does not deliver ash brown. How do you go about to get a refund if the seller closes your request without even an explanation? and obviously I cannot return a product such as a hair coloring agent.