If an infant fails the test in the left ear, there are two possibilities: first, because there is a foreign body blocking the external ear canal, such as earwax, or secretions left after birth blocking the external ear canal, or inflammation or fluid in the middle ear, which can cause the hearing test to fail; second, the child does have deafness in the left ear itself, such as genetic mutation or hereditary deafness, in this case it is recommended to first go to If there is no foreign body in the external ear canal, it is recommended that the child be rechecked 42 days after the test, and if the child does not pass the test in 42 days, it is recommended that the child be rechecked again in about 3 months. In general, when the child is about 6 months old, it is important to further check whether there is deafness in the ear, and if there is deafness, timely intervention is needed.