Why does it say “Approval Required” next to the Inmate’s name?

Why does it say "Approval Required" next to the Inmate's name?

    Some correctional facilities require visitors to be on the inmate’s approved visitors list. In order a schedule a visit with the inmate, you will need to inform the inmate or your name and visitor id. The facility will then place you on the inmate’s approved visitor list. Once you are placed on that list you will receive an email notification indicating that you are now approved to schedule visits with the inmate.