Wifi is not working

Hi all,
I am trying to access wifi on my board running on ubuntu core.

nmcli d

DEVICE TYPE STATE CONNECTION
eth0 ethernet unavailable –
eth1 ethernet unavailable –
sit0 iptunnel unmanaged –
lo loopback unmanaged –
wlan0 wifi unmanaged –

i followed all steps those are on this link “https://docs.ubuntu.com/core/en/stacks/network/network-manager/docs/configure-wifi-connections
But it always show wlan0 unmanaged how i resolve it.