or save yourself the trouble
To restart Shelfy, simply press and hold the middle button for 10 seconds.
During the process, the LEDs around the button, will flash orange.
Hold down until the LEDs have stopped flashing.
After restarting, the device will restart in purification mode.
Note: On rare occasions the LEDs may not flash or may behave differently. This behavior, however, does not preclude the success of the reboot procedure.