Hello everyone! Could you please tell me how you humidify the air in a…

Hello everyone! Could you please tell me how you humidify the air in a room with a child? The hygrometer shows about 20% humidity, that's all, always dryness in the mouth and nose for both of us. We bought an expensive ultrasonic humidifier, every time I turn it on, there is a tingling sensation from it. We fill it with either bottled or boiled water. Batteries are off (in our apartment building very insulated walls). Yesterday I put basins with water and a dryer with towels, it became 27%, still not enough;(. Is there something I haven't tried or am doing wrong?