Problem about navisworks export datasmith

Hi Sir/ Miss,

I have a problem about export Datasmith from Navisworks to Unreal. Some elements become “Object_0” items. And it doesn’t change with merge 0 and 1 level when export Datasmith.

The items under “Pipe Fittings > PPF-CSP-BBC-Elbow-Welded”. I have no idea why these items become “Object_0”. Other items under “Site > STE-STU-BBC-Dav_Chamber” is normal.

In merged 1 level model, items under PPF-CSP-BBC-Elbow-Welded still named “Object_0”. Items under STE-STU-BBC-Dav_Chamber named “Standard_0” which working fine.

What is the problems make the items become “Object_0”?

Regards,

Anyone have same problem?