how can i lock an mac address to an ip address i have a AR750s
Would you explain what you mean? It could be a reference to DHCP, the ARP table, another host, or a few other things.
To “lock” a device to a specific IP you can use the “Static IP Address Binding”. You can find it in the GL UI in the More Settings → Lan IP page.
The device will get the same IP every time, but it does not prevent the device from manually setting an IP and overriding your router setting though.
Thanks have a great day