code: public void changeConfiguration(ChargingStationId chargingStationId, ConfigurationItem configurationItem, CorrelationToken correlationToken) {
          Changeconfiguration changeConfigurationRequest = new Changeconfiguration();
          changeConfigurationRequest.setKey(configurationItem.getKey());
          changeConfigurationRequest.setValue(configurationItem.getValue());
  
          responseHandlers.put(correlationToken.getToken(), new ChangeConfigurationResponseHandler(configurationItem, correlationToken));
  
          WampMessage wampMessage = new WampMessage(WampMessage.CALL, correlationToken.getToken(), MessageProcUri.CHANGE_CONFIGURATION, changeConfigurationRequest);
          sendWampMessage(wampMessage, chargingStationId);
      }
docs: Send a request to a charging station to change a configuration item.
  
  @param chargingStationId the charging station's id.
  @param configurationItem the configuration item to change.
  @param correlationToken  the token to correlate commands and events that belong together.