Seek the help of a psychologist or counselor, who can evaluate your son's condition and provide treatment advice.
You can consider consulting youth rehabilitation centers, which usually focus on dealing with teenagers' cell phone addiction and lying flat.
Contact your family doctor, who can provide you with information about local rehabilitation resources.
Try to establish open, understanding and supportive communication with your son, and try to understand his feelings and troubles.
Try to encourage him to take an active part in social activities, sports and other beneficial hobbies.
The most important thing is to help my son overcome this dilemma with professional help and family support.