First, if you don't clean it for a long time or apply it too thick, it will lead to blocked pores on your face and easily induce acne. Second, long-term application on the face will also cause the skin to be difficult to clean, and the pores will be difficult to breathe, detoxify and repair themselves, which will affect the skin. Thirdly, especially for oily skin, after using the sleep mask, the sebum secretion on the face may not be removed, causing various skin problems. Therefore, when using the sleep mask, we should pay attention to the correct method, don't apply it too thick, and wash it regularly, otherwise it will increase the burden on the skin.