Send Mac Address of user to freeradius

I working on AAA using freeradius and fortigate every things go fine but calling-station-id return user's ip address and I need to return user's mac address not ip 

how can I do that?

Acct-Status-Type = Start Acct-Session-Id = "3f8a2b25" User-Name = "drdd" NAS-Identifier = "ftg" Framed-IP-Address = 192.168.5.148 Fortinet-Client-IP-Address = 192.168.5.148 Fortinet-Vdom-Name = "root" Calling-Station-Id = "192.168.5.148" Event-Timestamp = "Dec 20 2017 10:41:46 +03"