Alexa - Turn Anonymous blocking on and off

Most of the time we would like anonymous blocking turned on to prevent all those sales calls. However once and a while we need to unblock quickly for an expected call from a doctor, teacher, etc. Alexa would make this easy to do quickly. Sometimes we really don’t have time to get to a computer and login to do this since this need is often last second. Just turn on and off the blocking. Don’t need to change where it goes when blocked.