Joomla access state variable in modules

How can I access my state variables in Joomla modules?

I usually do it like

$app = JFactory::getApplication();
$variable = $app->getUserState('com_mycomponent.view.filter.variable' ,'default');

      

        
        
        
      

    

But in the module, the result will be empty, or in this case it will be the default.

The module has a selection field. I need to save the selection input to display the selected value again after the page is submitted. Without this, the select box will be reset after the page is submitted.