The discoloration on my knee is getting worse. Is there a way to fix this?

I didn't used to care much about it, but lately I've been worried because my knees seem to be getting darker. Especially in the summer when I wear shorts or skirts, my knees look particularly dark, and it bothers me because it draws people's attention. I wonder if my skin tone is becoming uneven as I get older, and it feels like the discoloration is more noticeable than before.

So, I have tried managing it in various ways on my own. First, I consistently exfoliated my knees using a body scrub every time I showered. Since I heard that scrubbing hard with an exfoliating towel can actually be irritating, I used a gentle scrub about once or twice a week. Also, because I heard that moisturizing is important, I applied a generous amount of body lotion after showering. Specifically for the knee area, I purchased a cream with whitening properties and applied it once more before bed. When going out, I made an effort to apply lotion frequently to prevent my knees from drying out, and I am also making an effort to reduce my habit of sitting with my knees on the floor.

I have been consistently taking care of it like this for a few months, but I feel a bit frustrated because it doesn't seem to have brightened as noticeably as I had hoped. I am wondering if knee discoloration can be improved at a dermatology clinic using methods like lasers or whitening treatments, or if I need to continue my current care routine for a longer period. I would like to hear advice from anyone who has had a similar experience or found effective methods.