code: public void uncheck() {
          getDispatcher().beforeUncheck(this);
          
          RemoteWebElement e = (RemoteWebElement) getElement();
          while (e.isSelected()) {
              e.click();
          }
          if (Config.getBoolConfigProperty(ConfigProperty.ENABLE_GUI_LOGGING)) {
              logUIAction(UIActions.UNCHECKED);
          }
          
          getDispatcher().afterUncheck(this);
      }
docs: The CheckBox uncheck function It invokes SeLion session to handle the uncheck action against the element.