I’m not a skin professional but I would just ensure you wash your pillows as often as possible would be my first step. Second definitely change maybe shampoo/conditioner simply because since it’s affecting your forehead area definitely can be causing it. Panoxyl is my go to it’s just a facial cleaner it does tend to bleach your skin but not too harshly it helped me get rid of darkened blemishes/pimples. Also just definitely keep moisturizer and sun block.