There are several points to consider when this occurs.
First, make sure you're in the correct Project. The current Project name is shown in the top right of the navigation menu, or on your Dashboard.
You can also verify if references are assigned to you by looking at the User Workload report in the Reports menu, and selecting the appropriate Level. If you do not have access to this report, ask your Project Administrator to confirm that the references are assigned to you.
Lastly, make sure there are references in your Project and at that Level - if neither is the case, the references and Level will not be displayed on your Dashboard.