Whenever adding countries, or configuring country tariffs, please make certain to not only add the zone/country, you'll next have to
- Confirm this action [click button: "OK"], then
- close the pop-up with the Zones/Tariffs [click button: "Sluiten"/"Fermer"/"Close"], and then
- Save your configuration [click button: "Configuratie opslaan"/"Sauver la configuration"/"Save configuration"]
Please mind that, should you forget to save your configuration and switch to another screen or menu-item, then your changes will not be saved and, consequently, are lost.
You then have no choice, but to to re-enter your configuration.