Hello ,
Thank you for posting in the community and sorry to hear about the troubles. We would need further information from you to best investigate this issue you are facing.
Are you using Datasmith exporter plugin for Revit or fbx format to import the contents from Revit?
What version of Revit and the plugin are using?
The best thing would be to report a bug by using the [ contact us ] button from the home page or by following this link:
https://twinmotionhelp.epicgames.com/s/case-community-page
Kind regards,
Vincent B.