ok so here comes the Bad news !
What has happened is the foam insulation inside the door has started to breakdown .
And has allowed the water line to freeze .
YOu only have to ways to take care of the issue .
One is cheap but it will happen again .
The second is the actual factory repair ,but expensive .
The first one is to turn the unit OFF with the freezer door open to defrost the line and allow the insulation to warm up , and then it could work for a day or 6 months.
The Second is to replace the entire freezer door .
It comes with all the dispenser parts , gasket .the only thing that is swapped from old to new is the door handle and the inner door shelf brackets .
Now I hope you are setting down ! here is a link to the part with PRICE