Hi ulao... from what I can understand, your system hair is now a bit too dark compared to your own and won`t `lighten`up for you ? The easiest solution would be to darken/ deepen your growing hair to match it..... coloring hair can be tricky as you`ve discovered....system/treated hair really `grabs` color rapidly and can deepen very quickly compared to growing hair.... normally [disregarding instructions on the pack] it`s best not to leave those `commercial` coloring products on/in system hair for more than 3 or 4 minutes at most....... it`s probably going to be a bit easier to do as I suggest rather than subject your system to any more `abuse` and all your colleagues may notice is that your [overall] hair looks a bit `darker` ..... try leaving it on your own hair for 8-10 minutes then rinse out/dry the hair/ sit the system on and see how it all looks......you can always go a shade deeper again on your growing hair if you think it`s still too light in comparison with the system...... it`s a real hassle when things like this happen but I think all wearers experience it eventually but it`s usually from normal oxidation by sun and shampooing etc..... give your system and growing hair a generous application of conditioner too to counteract the negative effects of coloring-chemicals.....hope that helps... Paul.