message: Check for empty string
diff: @@ -1021,24 +1021,24 @@ export default class OCPIUtilsService {
  return 'Tarif_Standard';
  }
  // Connector?
  - if (connector.tariffID) {
  + if (!Utils.isNullOrEmptyString(connector.tariffID)) {
  return connector.tariffID;
  }
  // Charging Station?
  - if (chargingStation.tariffID) {
  + if (!Utils.isNullOrEmptyString(chargingStation.tariffID)) {
  return chargingStation.tariffID;
  }
  // Site Area?
  - if (chargingStation.siteArea?.tariffID) {
  + if (!Utils.isNullOrEmptyString(chargingStation.siteArea?.tariffID)) {
  return chargingStation.siteArea.tariffID;
  }
  // Site?
  - if (chargingStation.site?.tariffID) {
  + if (!Utils.isNullOrEmptyString(chargingStation.site?.tariffID)) {
  return chargingStation.site.tariffID;
  }
  // Tenant?
  const ocpiSettings = await SettingStorage.getOCPISettings(tenant);
  - if (ocpiSettings?.ocpi?.tariffID) {
  + if (!Utils.isNullOrEmptyString(ocpiSettings?.ocpi?.tariffID)) {
  return ocpiSettings.ocpi.tariffID;
  }
  // Default.
  