setting up firewall with UfW

I am trying to setup firewall on my OMV5 setup using ufw only because I have used it a few times in the past with no issues. having set the default incoming/outgoing to "deny" and allowing only port 80 for OMV web UI and 443 for SSH. However for some reason I am still able to access some docker containers (e.g. Portainer port 9000). Can someone explain to me what am I missing here? IN the past when i setup ufw to allow one port and enable it, all other connections immediately drop out.