Fortigate 300D - 2 WAN link

Hello Experts

I need your help !!! 

I have Fortigate 300D and I have 2 Wan Link. My setup is as below.

Port 1 - Staff ISP (WAN1) - Manual Connection to ISP

Port 2 - Staff Lan - DHCP on  192.168.3.x

Port 3 - Student ISP (WAN1) - DHCP Connection to ISP

Port 4 - Student Lan - DHCP on  192.168.4.x

Static Route

Destination - 0.0.0.0

Gateway - WAN 1 Router

Interface - Port 1

Policy Route

For Staff

Incoming - Port 2 -- Outgoing Port 1 --- Source 192.168.3. x Destionation 0.0.0.0 / 0.0.0.0

For Student

Incoming - Port 4 -- Outgoing Port 3 --- Source 192.168.4. x Destionation 0.0.0.0 / 0.0.0.0

Ipv4 Route

Allowed all for both the networks.

Problem:

I have static Ip on Port 1 and I allowed HTTPS so I can connect to the firewall remotely. but as soon as I plug the Student WAN into port 3 then my remote connections to Firewall drops. but the Internet at school is always up and running.

Troubleshooting

I have changed the port for WAN2 and tried still I can ping WAN 1 IP or remote in.

I have disabled the policy route for Student network still no luck.

I have removed the dhcp scope from port 4  still no luck.

Thanks in advance for sharing your knowledge for this particular problem.

Mustafa