ipmacbinding not working in wireless network

I have a fortigate firewall(v5.2.3,build670), and i create two interface in firewall.

one interface is wired, connect to switch and wired client.

another interface is wireless, connect to fortiap(FortiAP-221C v5.2,build0240,150507).

i want to enable ipmacbinding in fortigate firewall, this is my configuration.

config firewall ipmacbinding setting     set bindthroughfw enable     set bindtofw enable     set undefinedhost block end

config firewall ipmacbinding table     edit 1         set ip <ip address>         set mac <mac address>         set name <name>         set status enable     next end

config system interface

    edit WiredNetwork

        set ipmac enable

end

config system interface

    edit WirelessNetwork

        set ipmac enable

end

wired network is fine in this configuration, but wireless network not working.

any undefined wireless host can access interface through firewall.

please help me, thanks a lot.