To reset the HomeKit configuration of the Internet Bridge, please follow these steps:
Remove the device from the Apple Home app.
Make sure the Internet Bridge is powered.
Press and hold the factory reset button on the backside of the Internet Bridge for at least 10 seconds until all LEDs on it start flashing. You can use a pen or any other pointed object to do this.
This will remove all the Homekit data from the Internet Bridge. The LEDs will flash five times to confirm a successful reset.
Set up the Internet Bridge with the Apple Home app again.
Please note: This process only clears the HomeKit settings of the device. All other information, like tado° rooms and the pairing between devices, will not be deleted.