Home Assistant - 404: Not Found ("Home Assistant CLI" access available)

I am running Home Assistant from a Proxmox VM. Suddenly I can’t access the web interface. I get the message “404: Not Found”

I never got to setup an SSH server but I can access the “Home Assistant CLI” from Proxmox. I have never used to “Home Assistant CLI” before. Can someone help me with navigating this CLI to print some information that could be used to get the web interface up and running again? Is it possible to setup SSH access from the “Home Assistant CLI”?