There are many reasons why you can still express milk after two years of weaning, as follows: 1. milk accumulation, milk has not been completely discharged and gathered in the breast, which can be observed by yourself without treatment, or you can assist the breast pump to suck out the milk that exists in the breast. 2. breast hyperplasia, endocrine disorders leading to breast hyperplasia, breast duct deformity milk is difficult to discharge. Patients with breast enlargement can see hard, smooth, clear and mobile breast lumps with a hard texture. The pain occurs before and during menstruation and disappears after menstruation. The patient should take masturbation treatment, and if necessary, surgery. 3. Pituitary tumors, most of which are benign intracranial tumors, occur in middle-aged and elderly people, and cause visual impairment and increased cranial pressure and endocrine disorders.