There could be a few reasons why this may happen:
- Check any prompt (dynamic) filters that may be applied to the report. If there are any prompt (dynamic) filters applied, they will show up under the Report's title.
- Then check the report's definition (Edit Report -> Filters) to ensure that all implicit filters are correctly setup. Filters are used to pare down your report until it only shows the data that you want. Sometimes, unwanted filters might prevent showing you the data you need to see.
- Finally, you might need to check with your administration if you have access to view that data. Unless you have access to view the data presented in the Report, you will not be able to see the data even if the report is shared with you.