Unfortunately without a sample DXF file to review or a description of the settings used during DXF import, it's very difficult to provide any technical assistance. I would recommend the following:
1. Review our DXF Conversion guidelines, which explains all critical steps to properly convert any DXF. https://www.numericalinnovations.com/blogs/news/6116174-dxf-dwg-to-gerber-conversion-guidelines
2. Try our product FAB 3000 which is our primary tool for converting DXF to Gerber. FAB 3000 is specificlaly built for Gerber data and has a wider range of editing commands, etc. https://www.numericalinnovations.com/collections/fab-3000-gerber-cam
If you can provide me a sample DXF file, I'll be happy to create a tutorial movie showing exactly how to perform the DXF to Gerber conversion.