How to get instant reverse to update existing classes?

I am doing Instant Reverse for a .Net exe project. It works fine the very first time a class is created. However, after making changes to the class in the source code and I then attempt to do another instant reverse in order for the class in the model to be updated, it creates a second class in a new class diagram instead of updating the existing class in the existing class diagram. I’ve chosen the “Update duplicate classes” option but that has no effect. I’ve even done a bare bones, instant reverse a class from an .exe file and then using the same .exe file instant reverse the same class again. It always creates a 2nd class and a 2nd class diagram. What am I doing wrong or is this capability not supported?