The buttons on the left side of the display operate, but the buttons on the right do nothing when I press them. Regenerate and salt level work, Select, arrow keys, and Water Flow do not work. I unplugged the machine for a few seconds, but that did not help. I am afraid that if I leave the unit unplugged for a long time, my settings will reset and the buttons still will not work, so I won't be able to input my settings again.