My heels are turning white

It's not dead skin, but my heels are white.

I wonder if it's athlete's foot. It feels like it's getting worse since I've been wearing sandals.

Is there perhaps a good way?

I use an exfoliator to scrub the back, but it is a care method that completely removes dead skin cells.

Isn't there any? I apply body cream, but it's only temporary; if I stop applying it, it turns white again.