Can Skin Lightening remove this “hyperpigmentation” between my intergluteal cleft (butt crack) area? (photos)

I’ve been struggling for the past 3 years with this severe darker tonality between my butt cheeks. Have conducted research for so much now Ive lost my mind into it, from not knowing whether it is Acanthosis nigricans or post inflammatory hyperpigmentation. It has never hurt or itched so therefore I don’t know what this truly is & after do much years I’m so tired of seeing this area such darker than my normal skin. Literally like 4 tones darker. I’d greatly appreciate if I could receive solutions