A 29-year-old female patient complains of peeling, dryness and burning of the lower lip. Objectively: on the vermilion border of lip there are multiple gray scales with tightly attached center and peeling off edges. The scales are found all across the mouth and from the wet-dry line to the middle of the lip. The skin is not affected. Scales removal doesn't lead to erosions. The patient has the lability of psychoemotional sphere. What is the most likely diagnosis?