Water leaks when trying to dispense Water from Daewoo Fridge/freezer?

I have an American style DAEWOO Fridge freezer which dispenses water/ice/crushed ice. Every time we try to dispense water the water leaks instead from the bottom left (freezer) door.
The water filter at top BACK of fridge maybe due for replacement but I cannot fathom what has happened.
How can I investigate?
I have read most of previous comments but I haven't come across a similar problem.