We have a GE Profile dishwasher Model pdw7880n00ss that was new to the house, it’s about 7 years old. This morning we went to wash a load of dishes and it won’t start. The “normal” button lights up and it beeps as it should when the door is fully closed. But the “start” button doesn’t light up and pressing it does nothing. The other buttons on the control panel seem to be working. Any idea what could be wrong?