Whether it's a skin problem or a hair problem depends on whether you start to get oil from the hair roots (that is, scalp problems) or what. I always start from the root of my hair, and my hair is soft and thin. I wash it once every two days at most, otherwise my hair will be as oily as it was just washed. But in this case, you can't wash it frequently, and the more you wash it, the faster it will get oily. A friend who is studying at the University of Traditional Chinese Medicine told me that in this case, you should soak your feet in hot water for at least half an hour every night, and the water temperature should be hot. If it is hair oil, blow your hair with a hair dryer (this is what the barber shop owner told me). I don't think it's hereditary. I hope it helps you.