Got x.x.x.x send invalid reponse


I have installed NextCloud with Apache2 as backend in Ubuntu 20.04 server and a Collabora Office from deb package (not Docker) running with same Apache2 as a reverse proxy port 8080. Opening http://x.x.x.x.8080/hosting/discovery got proper XML output. Unfortunately whenever I open any document in NextCloud, I got “Got x.x.x.x send invalid response”. What’s wrong here?

Other note:

  • No SSL at all as I want to run the web app remotely by VPN
  • 000-default.conf has been disabled but opening http://x.x.x.x:8080 show me default Apache2 Ubuntu page