The device may have been logged off by mistake. If the DECT button on the RolloTron is pressed for more than 2 seconds, the logoff process starts. The LED flashes red and the device logs itself off from the Fritz!Box.
You can check whether the connection to the Fritz!Box is established by briefly tapping the DECT button. If the LED is green, the connection is still established.
If the LED is red, the RolloTron DECT must be re-registered.
To do this, press the DECT button on the RolloTron for more than 2 seconds. The LED flashes green.
Now press the DECT button on the Fritz!Box for more than 6 seconds.
If the registration is valid, the LED on the RolloTron will light up green for a few seconds.