[AppRepair]

There could be a problem with the valve but it is only one of a few things it could be, or even a combination of troubles. Depending on the age of the water lines and fill valve there may be build up that is decreasing your water supply to the ice maker cells that form the ice. If your ice maker is not working at all, it sounds like it's not getting water. I would start with the valve cleaning or replacement and see if that fixes the issue. If not, consider checking the thermostat to the freezer. It should be kept at zero degrees.

Personally, I don't think harvest mode is your problem. Harvest mode is when the ice has been formed and is ready to be dumped from the cells into the holding container. A small amount of heat is applied to the cells to allow the ice to "pop" out before the cells are refilled to freeze the next batch.