How to Lighten Remaining Skin Pigment After Mole Removal (Shave Method -- Due to Location Cutting in is Not an Option)? (photo)

I had a mole on my left upper lip shave removed about 7 years ago. For the first few years it was very light and almost blended into my skin. Recently it has become much darker and it is starting to bother me again (especially when people mistake it for dirt or marker since it flat against my skin). What is the method to lighten this "scar" or "intradermal melanocytic nevus?" I do not want to cut the mole out as it will ruin the shape of my lip (I was told it is very deep). Thank you for your help!