Door Reset
If the restart did not work due to the interruption of the power supply, there is a small reset button between the metal sheet and the white battery plug in the area to the right above the white component that protrudes slightly from the cover plate. Here you can carefully press the rocker with a ballpoint pen or similar. The restart was successful if the red circle in the display lights up afterwards. After a rattling noise, the animal door is reinitialized and ready for operation.
Alternatively, you could unplug the white battery plug with the red and black cables (Caution! This has a plug lock on the bottom, which is best pressed with a small screwdriver when unplugging) and then unplug the power pack from the socket until all the lights on the display have gone out. Then plug the white plug and the power pack back in (if the power pack is flush-mounted, briefly switch off the lock).