Water dispenser on Firdge frezzer not working

Scruff

Have an American style Samsung Fridge Freezer. Went away for a night and freezer door was left ever so slightly ajar. Came back to find ice in ice maker at the top had melted, puddle on floor and water dispenser not working.
Clean mess, defrosted food and tested all parts of water dispenser from water pipe into fridge and out pipe and it seems that the pipe from the pump on the fridge to the front of the fridge where it can be disconnected to take off the door is where the problem is.
Could it be the case that the pipe has frozen due to cooling system going constantly to compensate for open freezer door? Ice maker water pipe which doesnt go under it is fine.
Was thinking of disconnecting fridge from water and elec and blasting a hair dryer through the back where the pipe goes from the pump/switch under it..

I suppose that the first thing to try would be to switch off and defrost the entire unit, then afterwards turn on and let it settle and try the water dispenser again.
Don't blast it with a hair dryer, some of the plastic may not be able to withstand the heat.