Can armpit hyperpigmentation improve?

After getting married, I lost a lot but only gained a child, haha.

It's hard to give birth and raise a child, but my body too.

I think it was also very difficult to change from the way things used to be.

I have developed underarm pigmentation after having a baby.

I usually hear that things get better after pregnancy, but it doesn't seem to be improving at all.

When I wear a sleeveless shirt at home or go somewhere to exercise in the summer, my attention is entirely focused on that area. Even when exercising, I can't wear sleeveless shirts that others wear. I'm afraid to go to the hospital, so what are some ways to improve this at home?

Is there any way you could tell me about applying it or any other method?

I don't want to see it, but I'll upload the picture.