fun autoLogout() {
        // get current fragment
        val navHostFragment = supportFragmentManager
            .findFragmentById(R.id.nav_host_fragment) as NavHostFragment
        val currFragment = navHostFragment.childFragmentManager.fragments[0]

        val mainMenuFragment = R.id.mainMenuFragment
        val settingsFragment = R.id.settingsFragment
        val functionFragment = R.id.functionFragment

        when (currFragment.id) {
            mainMenuFragment -> currFragment.findNavController().navigate(R.id.action_settingsFragment_to_loginFragment)
            settingsFragment -> currFragment.findNavController().navigate(R.id.action_mainMenuFragment_to_loginFragment)
            functionFragment -> currFragment.findNavController().navigate(R.id.action_functionFragment_to_loginFragment)
            else -> Log.e("MainActivity", "currFragment = $currFragment \n" +
                    "current fragment id = ${currFragment.id}. \n" +
                    "mainMenuFragment = $mainMenuFragment \n" +
                    "settingsFragment = $settingsFragment \n" +
                    "functionFragment = $functionFragment \n" +
                    "It did not logout")
        }
}