Redirect External Port to Internal IP

Before Xfinity, I used to use a router behind the cable modem and connect to different computers on my LAN using RDP. I would use:

publicIP:port1 and it is sent to lanIP1:localPort1

publicIP:port2 -> lanIP2:localPort2

Now and with Xfinity modem/router, I am unable to do that.

So if I have two machines on my LAN that have remote desktop with port 3389, I cannot connect to both. Xfinity port forwarding doesn't allow that out of the box.

Is there a different way I can port forward outside port to specific LAN:Port ?

thanks,