Water Dispenser Issue

Dispenser will not work period. Ice maker features will dispense all types,night light works as well. I can hear a single "click" when depressing the flange to try to dispense water. Have not seen any display from the filter that it needs replacement.

As for testing flow through the water valve up to the point where the supply lines turns up into the freezer door, it looks like a quick disconnect fitting.If so, will I be able to reinsert the line coming from the water valve to the disconnect block should I disconnect it to determine if I am getting flow through the valve?

Second, if water is in fact getting through then it sounds like there might be a blockage due to possible freezing. If I want to check this by trying to thaw the line with a hair dryer, where on the freezer door should I direct the heat?

Thanks

PS If allowed and someone is willing I am more than willing to call directly.