Thank you for your question.
This is an AutoCAD export issue. There is a discussion group that focuses specifically on AutoCAD. I suggest that you can post your question in that group.
Please try to follow the link below for your convenience.
Auto CAD
Please let me know if I can be of any further assistance
-Leon Li
ADR/DWF Custom Support
Leon Li
SQA Engineer
PSEB-GE-ACRD PSEB
Autodesk, Inc.