Ganti mac ubnt via cmd

Ganti mac ubnt via cmd
I have used below commands, but not able to change the mac address..please help

1.

ifconfig ath0 down
ifconfig ath0 hw ether XX:XX:XX:XX:XX:XX (YOUR MAC)
ifconfig ath0 up
vi /etc/persistent/rc.poststart
Result:- MAC changed but after reboot it’s come to its original mac address. Not able to save MAC address
2.
ifconfig wlan down
ifconfig wlan hw ether XX:XX:XX:XX:XX:XX
ifconfig wlan enable
Result:- These commands not working.
3.
echo "ifconfig br0 down;
ifconfig wifi0 down;
ifconfig wifi0 hw ether XX:XX:XX:XX:XX:XX;
ifconfig wifi0 up;
ifconfig br0 up"
> /etc/persistent/rc.prestart && cfgmtd -w -p /etc/ ;
Reboot
Result:- MAC address not changed