Error: CSV import is not updating existing records

The CSV import facility is for the import of new records into the administration system.  It cannot be used to update existing records. If existing records are found then they are ignored and are not updated.

If you want an automated way of updating existing customer records then you need to purchase the eCommerce interface to do this. More information can be found at http://www.locklizard.com/product-add-ons.htm.