Hi Sir.... I Have Acne And Pigmentation That Made Me

Hi sir....
I have acne and pigmentation that made me desp.. so i used melacare for the last one month... realy exited results made melacare..but after stoping melacare my skin became dark.. my skin is too sensitive and i cant use even a sunsreen lotion or pwder rather than Himalaya baby powder... if i use any of the cosmetics soon after my face prone for the acne.... plz give me a sugession...