It may be necessary to place the Smarthome controller closer to the router (even if the distance is not that high)
Even if the Smarthome controller is within half a meter of the router, this may be the cause, increase the distance in this case.
If you have multiple routers, you can best install the Smarthome controller on the Wi-Fi of the first router on your network (that is, the router is first on the internet connection)
Never use your guest network for this.
Logging in to the Smarthome controller on another (optional) router, Wifi amplifier, or similar equipment may cause the Smarthome controller to not work properly.

Even if you have a very slow Wifi / Internet connection at the time, the message "offline" may appear.