OCSP response is 404 : File or directory not found

I have Windows Server 2012 working as OCSP online responder. Config seems to be fine as I have tested multiple times. I am trying to send OCSP request from Firewall which is a HTTP POST request and getting 404: file or directory not found in response, however, that same certificate exists on the server.(i.e In Issued list).

Let me know what all I can check because I am not the master of Microsoft server.

Also, no event logs are getting generated in Windows logs--Application and System folder.Any help would be appreciated.

Link: http://X.X.X.X/ocsp