Webpage available through haproxy frontend port 443 but not on a custom frontend port

I need a website to listen on port 8181. When I have the backend setup to 8181 and frontend to 443 the webpage loads fine but when I change the frontend to 8181 it gives 503 anyideas on what i am missing here

Make sure you have a corresponding firewall rule in pfsense to allow access to that port.