Try increasing the tolerance, mesh resolution, triangulation before exporting into STL. Exporting at 0.01mm tolerance and 5 degree angle resolution is recommended. This can be easily adjusted under export option in most CAD software. To avoid any difficulty in file processing, it is advisable not to export files at excessively high resolutions as it does not enhance print resolution. If you encounter any problems, please send us your original CAD format through, and our team will be happy to assist you with it.