If it is a girl, it may be fungal vaginitis. I've had enough. I have to go to the hospital. Hygienic products should still be washed by hand. Note that if it is cloudy or rainy, the dried underwear can only be worn by blowing it with a hair dryer. Even if it gets better, it may recur.

I suggest you go to the hospital for a checkup. Don't apply ointment casually. It will be very troublesome.