Report cannot be displayed in Dashboard through App under a Fabric workspace

[JohnnyTWW]

I created some simple reports using import dataset in PowerBI.  Then, I created a Dashboard and link to these reports.  Everything is working. I can select the Dashboard directly to show the reports' content.
Then, I create App in the workspace to select the Dashboard.  Under the content and editing, the reports are showing without any problem.  I comfirmed the access right and make sure the reports or dashboard can be accessed.  It set correctly on the Audience tag for the user and the "eye" icon is open.
But the report cannot be showed through from Dashboard I select from the app. The Report area is just empty blank page.
But if I added the reports into a new session, the reports shows on both dashboard and under the new session in the App.  
If I remove the new session or close the eye icon of Audience tag, and keep the dashboard, the reports under the dashboard will show "The report shown in this tile doesn't exist or you don't have permission to view it."
Is it a known bug in powerBI?
How can I resolve this issue?  Thanks for any help!