Hi I don't have answers sorry. I just read your post and this is an issue for us as well. We have a side by side with ice/water in the door but the space is too narrow for a family member who is wheelchair bound to be able to access most of the items in it. We are going to get an all refrigerator all freezer pair because they will be wide enough for him to get close enough to get things...and the Whirlpool sidekicks have slide out shelves. But none of these have ice/water in the door. I love my crushed ice and not to mention the accessiblity of the ice and water in the door. I thought about an ice machine but then my husband told me that they have to be cleaned often because the temperature in an ice machine allows bacteria to form versus an ice machine in a freezer? I don't know much about it...just started researching. I don't understand why the manufacturers don't offer ice and water in the door on all refrigerator all freezer pairs. I saw there are some refrigerators with top freezers that have water in the door.

First thought is agreement with antss. Do you have an ice-maker in there? Suggest placing some ice-cubes in different parts of the freezer. The next time it happens, observe whether or not this melting/refreezing of the cubes is confined to single area or is happening throughout.

Yes it is a clear ice machine

Possibly the water inlet valve is seeping, slowly overflowing the mold, water dripping out of it freezes into a block. Can also be heavy mineral accumulation on the mold from hard water causing a type of capillary action to pull drips of water out to the same effect.