Duplex problem

I try to use robocfg to force the WAN interface to use 100 mbit full duplex. This is a requirement from the ISP. It negotiates to 100 mbit HALF duplex...

admin@RT-AC68U:/tmp/home/root# robocfg showports
Switch: enabled
Port 0: 100HD enabled stp: none vlan: 2 jumbo: off mac: 00:0a:41:65:84:3f
Port 1: 1000FD enabled stp: none vlan: 1 jumbo: off mac: 14:fe:b5:a4:b0:c8
Port 2: DOWN enabled stp: none vlan: 1 jumbo: off mac: 00:00:00:00:00:00
Port 3: DOWN enabled stp: none vlan: 1 jumbo:...

Duplex problem