Port forward problem

[hamdy]

hi guys
how r u all
i faced problem during the port forward using the GUI so i need help for u plz in that

pfsense LAN ip 192.168.1.1 and i have proxy server in the LAN side and it's ip is 192.168.1.2 and i need to make port forward on the pfsense machine to forward the traffic that come from my network "192.168.1.0/24 on the LAN side " to 3128 on the proxy server

i tried to make it by the GUI but it dosn't work , i think that the problem is that i must except the ip of the proxy server from the port forward rule , is that right ?
plz guys tell me how to make that and if it is the problem or no

thanks a alot