The Domotz agent lives on port 3000, as such, you need to add the port number to be able to access the Domotz Agent. If the device you installed the Domotz Agent is on IP address 192.168.1.100, you’d simply add: 3000 to get 192.168.1.100:3000. You should now be able to access the web UI of your Domotz Agent.
Note: If your device already has an app using port 3000, Domotz will automatically use the next available port, i.e. 3001. This works incrementally until a free port is available.