OPNWAF plugin not working correctly

[Support2U]

Hi all,

I have a question regarding the plugin os-OPNWAF.

We are using OPNSense (Business Edition) as firewall in front of our webservers and are trying to use OPNWAF to protect our websites which are hosted on IIS on MS server.

OPNWAF seems to be working because it gives us error message when trying to insert faulty strings, but we cannot access/forward to our (internal) websites.

The situation is as follows;

Made virtual server on OPNWAF named waf.xyz.com.
Made location with path '/' and remote destination www.xyz.com which is a website on 1 of our (internal) servers behind the firewall.
Response we are getting when accessing https://waf.xyz.com is  'Service Unavailable'.

Am I missing something?
Any hint/answer is much appreciated.