Dark skin color. on face. Help me?

I have been asking this question and taking treatment for my issue for a long time. But I haven't got any successful results yet. I am facing a skin problem that, my face colour is much darker than body color which is very visible. I had been using Skin Whitening cream for the last 3 years. When I use the cream, my skin becomes lighter in 2 - 3 weeks., when I stop it, my skin becomes darker. I cannot use any fairness  cream/serum/lotions on my face except the above mentioned Skin Whitening Cream. When I use any cream, my skin becomes darker. But I think I have had darker face skin for a long time. That's why I started to use Skin Whitening Cream. But still have facing this issue. Is there any permanent solution for this problem? Is their medicine to cure darkness of face? Is it better to meet a dermatologist or cosmetologist? I have no other medical condition. But recently I have found high level of bilirubin. Can someone help me?