If your export file looks something like this, continue reading to learn how to fix!
This is because the diamond export file downloads in CSV format where the decimal separator should be a . (period/full stop) instead of a , (comma)
If your decimal separator is comma instead of period/full stop, here's how to update it
Open an blank Excel sheet
Go to File > Options > Advanced > Editing Options >
Check the box: Use System Separators
Decimal separator is .
Thousands separator is ,
Now go to your computer's Control Panel
Formats > Click Additional settings
Set List Separator is set to , (comma) > OK