You can view all assessments created in the workspace in the overview in the administration interface. Therefore, make sure that you are logged into the correct workspace. Also, check if you have set filters that show only the assessments with a corresponding status, for example. By clicking on the filter options above the assessment overview, you can set or remove the filters.
If you have many assessments created, the assessment you want may not be on the first page. You can navigate by clicking "Next" or "Page Numbers" at the bottom of the page.