Skin discoloration?

Kirthi

Hey guys! So for the past few years since I’ve started threading my upper lip, I’ve noticed a lot of skin discoloration. With the hair gone, the skin in that area is lighter than my surrounding facial skin. I’m not sure how to change this/possibly make it darker to match my actual skin tone. I’ve added a photo for visuals. Does this happen to anyone else? And what tips do you have for this?