Hi Doctor, I Got Pigmentation On My Nose, Front Check

Hi Doctor, I got pigmentation on my nose, front check and all my face & body. There is more pigmentation on face than body. I went to laser treatment.Then I got clear skin but after one year I'm suffering with the same problem. There is no itching or pain. It became as a big problem for me. I'm 20 years old. I'm a BTech student. While going to college I'm using scarf. I did not have this problem upto my 10 yearof age .After this problem started. I need a solution for this problem. Is there permanent solution for this problem.