It’s an encoding issue on Excel’s end.
We export the file in UTF-8 which works with all the characters across all languages.
You need to edit the file in Excel or Google Sheets and save it as UTF-8. If you save in Excel using a different encoding, the special characters might be lost in the file.
So this issue is not in our plugin, it’s an issue on the software you used to edit the file outside WordPress. It’s outside our control.
Make sure you change Excel’s settings to edit files as utf-8 or edit using Google Sheets.