I received an email from NVC about upcoming interview appointment for my wife and step-daughter. It directs me to this site -> Interview Preparation (state.gov) I click on the link go to embassy La Paz. It says to register appointment online. I attempt to register both but when I enter their Case No it says not ready for appointment. Do I have to wait to do this? Also, it ask for the DS-260 number. Is that the Confirmation No on the DS-260?