Apache server with cloudflare tunnel

Hey guys, I am trying to make my apache server (running on rpi 4 at home) accessible to the world. I have a domain and I have set up a tunnel. The problem is that the apache server is displaying a flask application on my home network but a basic apache page on the domain. I would like to see the flask app on the domain as well. I dont know why is it not working. Thank for your help.