My only advice would be to avoid using the same iterator.. I think that you might be running in some overflow or some other type of memory issue. For the exercise you are doing, I would use GlideRecord.updateMultiple() as you aren't having any condit...

It's hard to determine from the pictures what exactly is happening.  But what can be seen is the following: The action "Get types of all fields" fails with an error. The error is stating that in the code execution this was evaluated: "undefined.issue...