I was referring to these two options highlighted in blue above, can you please confirm, if those are set as above?
Also, please note, Autodesk Inventor Reader mode does not support the CAD associativity, it is only supported in Autodesk Inventor Associative Geometry Interface which is not available with a student license, are you using a commercial license?
As a workaround, you can import additional geometry in a given Mechanical session, in addition to the previous one that you had in the Mechanical using Geometry Imports Folder. And then suppress or delete the old part and set up only the new modified part and its material and related contacts to the part.
-Aniket
You are navigating away from the AIS Discovery experience