CODE EXAMPLE FOR SHELL

Authentication required. System policy prevents WiFi scans

# Edit or crate a pkla file like
sudo nano /etc/polkit-1/localauthority/50-local.d/custom.pkla

#add folow content

[Allow Wifi Scan]
Identity=unix-user:*
Action=org.freedesktop.NetworkManager.wifi.scan;org.freedesktop.NetworkManager.enable-disable-wifi;org.freedesktop.NetworkManager.settings.modify.own;org.freedesktop.NetworkManager.settings.modify.system;org.freedesktop.NetworkManager.network-control
ResultAny=yes
ResultInactive=yes
ResultActive=yes