The main reason for entries not converted are related to inconsistent CSV format. i.e. some values may contain double quotes while other values do not have any quotes.
To fix this, you need to follow this article https://csvconverter.biz/blog/how-fix-csv-file-not-being-converted and re-export the CSV using quotes for all fields
If this doesn't work you can Report it by creating a new bug/issue on https://csvconverter.biz/project/issues. Don't forget to attach a copy of your CSV for investigation