Have you called the service number on the box of coloring? I have had a few color mishaps and the customer service reps are trained to know what to do.The last time I had a mishap they told NOT to recolor as it makes it worse. They said to use a cleansing shampoo, VO5 has one and to keep shampooing it every day . I would call the customer service number for the brand you used as they may have a different solution.
Good Luck