Why can't I import cad files?

2018 Pro - each time I try to import a CAD / dwg file it fails? I’m using AutoCAD 2018 lt.

SketchUp 2018’s CAD importer doesn’t import AutoCAD 2018 files. SU2018 was released before a newer importer was available. Save the CAD file as an older version in ACAD and then import into SketchUp.