Can you confirm there are no element bindings in play? If they are already there player will ‘update’ them but not save the new bindings.
If you aren’t sure what element bindings are, check this post: Element Binding in Revit.
There is also my AU class and associated documentation linked in there, and a if you’re just curious you can get a quick highlight starting around the 12:50 mark of the video here: Element Binding in Revit