Exporting to Autocad arc segments

Hi guys, I.m not using autocad so often because I like to work in Sketchup, but for a client I have to export some 3D designs to autocad. Apparently I have some troubles getting the right because when I send my dwg (or dxf) to my client they claim to see arcs and segments in my round objects. I’ve tried to export in parallel projection mode and with a top view and several option settings in the “safe file” window but nu results. Anyone out there who can give me some advice?

I work with Sketchup pro 2020 on Mac, and have to convert to autocad 2018.