Inside the freezer, behind the rear wall (number 11 in the diagram at the link below) is the evaporator coil.
Under that evaporator (number 22 below) is a drip pan (number 20) that collects the water created by the defrost cycle and routes it to a pan below the cabinet (number 8) for evaporation. That drain is plugged.
The easiest way to thaw the drain is to open the doors and unplug the refrigerator for 24 hours. Of course, this will displace the food for 24 hours, which may be a bit inconvenient. The other option is to remove all freezer contents, shelves and the rear panel (inside the freezer) to access the drain trough to manually thaw it with hot water only, nothing sharp! Once that drain has been cleared, you should have no more water issues.
The problem is a known one and an updated drain tube has been designed and I would strongly recommend you install the updated it, available below.
The video at the link below shows how it is replaced!
Please know that I am compensated by the site only after you offer a rating at the top of the page. It is my goal to provide 5 star service!
Please know I am here if you have follow up questions! Thank you so much!