After adding the Internet Bridge to an Apple Home, or a new tado° device to an existing system, it may take up to 40 minutes before the device shows up in the Home app.
If a tado° device still does not show, or is marked on the Apple Home app with “No response” or “Unavailable”, try the following:
Ensure that the Internet Bridge is connected to Router and powered, and that the “router” LED is solid.
Make sure the iPhone or iPad is connected to the same Router as the Internet Bridge.
Force close the Home app and open it again. This will read all characteristics of all devices and update the values.
Disable Wi-Fi on the iOS device for 30 seconds and then re-connect to the WiFi.
Finally, try deleting the Internet Bridge from the Home app and perform a HomeKit reset on the Internet Bridge. Then set up HomeKit again.