Revit - Lost TM assigned materials when moving between different files of a project

Hello,

I have been working on a project in revit and twinmotion via direct link.

I had setup the revit model with materials etc and then presented the proposals to clients.

Following feedback and to incorporate the changes requested I created a copy of the revit file (to not loose the previous iteration) and updated the new copy of the revit model as necessary. When opening this into twinmotion (and selecting the previous associated TM file) I found all of the materials etc had been lost - is there a way to ensure the materials from the previous twin motion file are applied to the new one?

When opening the updated model it had lost all materials settings, even on elements that had not been altered etc

Kind regards