Nginx reverse proxy connection timeout

Hi guys!
I get a hAPac2 and nginx reverse proxy in my network with port forwarding done on 80 and 443 on the nginx reverse proxy.

From outside of my network I can reach my webserver through the nginx reverse proxy.

What is not working is when I try to reach website from the same network of the reverse proxy and the webservers.
If I modify the hosts file to point directly the nginx reverse proxy, it’s working.

Here is the configuration of my DNS :

                      servers: 202.22.235.3
              dynamic-servers: 8.8.8.8,1.1.1.1
        allow-remote-requests: yes
          max-udp-packet-size: 4096
         query-server-timeout: 2s
          query-total-timeout: 10s
       max-concurrent-queries: 100
  max-concurrent-tcp-sessions: 20
                   cache-size: 2048KiB
                cache-max-ttl: 1w
                   cache-used: 179KiB

Do you have a clue of what is not working in my conf?
How can I share all the config without giving secret informations (passwords etc)?
Thanks for your help

Start reading here: https://wiki.mikrotik.com/wiki/Hairpin_NAT