Problem Creating Interface for Multi-WAN

[Craeft]

Hey everyone. I'm pretty new here, using 2.1.5.

I am trying to set it up for multiWAN for load balance and failover. Unfortunately, everyone I see post about this says to go to INTERFACE > ASSIGN and then click on the + sign to make a new interface.  However, there is no such option.  When I click on INTERFACE, I have only (assign), WAN, and LAN as options and no way to create a new one. In the area where it lists WAN and LAN, there is no + icon.
Am I missing something here? 
Any assistance would be most welcome.

Thanks in advane.

[Derelict]

There is no '+' if there are no unassigned interfaces.  What type of card has the port that isn't showing up?  Be sure it's supported.

[Craeft]

@Derelict:

There is no '+' if there are no unassigned interfaces.  What type of card has the port that isn't showing up?  Be sure it's supported.

Hey Derelict.  Thanks for the reply.
Got in touch with the one currently near the server and it's running on i8254 which is apparently supported (from what I can find).

[Derelict]

You'll have to look through ifconfig -a ,  /var/log/dmesg.boot , etc and see why it's not available for selection.

[Craeft]

@Derelict:

You'll have to look through ifconfig -a ,  /var/log/dmesg.boot , etc and see why it's not available for selection.

You're awesome, Derelict. I will delve into that when I can next get my butt back near the machine.