I want to solve my acne pigmentation problem in the mirror.

Lately, every time I wake up in the morning and wash my face, I'm surprised to see my skin in a completely different state than before. Before, whenever something got on my skin, it would clear up in a matter of days, but now, once it settles in, it shows no signs of going away. The dark acne pigmentation around my cheeks in particular makes my skin look dull, even after layering on makeup. It's frustrating to look in the mirror. I've been consistently applying vitamin ampoules and slathering on whitening creams every night, but the acne pigmentation stubbornly lingers. I keep questioning myself, wondering if it's because my skin's regeneration rate has noticeably slowed over time, or if it's just my poor habits. Trying to cover it up with makeup makes my skin look too dull, and leaving it alone makes the acne pigmentation more noticeable. It makes me very self-conscious every time I go out. Has anyone else wisely addressed similar concerns regarding acne pigmentation, or have a special skincare routine you'd recommend?