We are sorry for the trouble. This is a known issue and has been reported by multiple users. This generally happens when the DWG/ DXF file is exported using a third-party application, not AutoCAD, or you have exported using an older version of AutoCAD. I will be happy to provide you with the Ai file for your DXF file. Would you mind sharing the download link to the file here or via DM with me in case confidential?
Kindly update the discussion if you still need assistance with it. We'd be happy to help.