Hi. You are probably suffering from vitiligo. You'll need to see a dermatologist near you or send pics on follow up chat for confirmation of diagnosis. Note the following:
A. Vitiligo is an immune condition. B. With medications or surgery it may be possible to bring back the skin colour- however the extent to which this may occur on different people varies. C. Certain questions of duration of the symptoms, whether currently increasing, etc need to be answered. D. You'll need topical and oral medications. E. This disorder is not dangerous apart from it's cosmetic problem. Hope this helps. Further queries may be sent on private follow up chat.