You are not seeing the content that you're expecting to see in the Navigation pane.
This issue can be caused by a corruption of the local cache. There are several methods to refresh the local cache in Remote Desktop Manager
Press CTRL + F5 on your keyboard.
Hold the CTRL key on your keyboard and click on the refresh button in the Quick Access Toolbar.
You can manage the local cache by doing a Vaccum , a Repair or a Delete