Quattro 2 Not detecting shore power

I installed a quattro 2 in an RV. It ran great most of the summer. About a week ago the customer had an L1 overload and it would not recognize the generator on input 1. I logged into the VRM and was able to reset the quattro 2 by running a redetect on the can bus system. The next day they moved to a park and connected to shore power. It ran until about 9:45 at night and then lost the shore power. It still has 120 split hitting the input 2 but it never recognized that it has power there. The generator on input one is getting them by for now but I am looking to help as to what happened to the input 2 side of the unit. Customer has another month on their trip and I am hoping to fix this without bringing them back to Arizona.