Hair Color Problem- "UnRed" product.?

Last night I bought chocolate brown hair color to put on my light brown (colored) hair. I naturally have light brown hair, but it has been dyed recently and I kept having orangeish red poke through. I do have a slight tint, but it used to not show up through color. I bought this "unred" color additive into the hair color (like you are supposed to), but it made my hair color have a slight red tint. This is the opposite of what was supposed to happen..did I do something wrong, or will it fade? Has anyone else used this product, or what can I do to stop the red? I am just trying to achieve a chocolate brown color.