Restrict DataDashBoards page from end user

Hi,

User is able to access the dashboard page by manipulating powerBI report viewer page (exp: /ReportViewer/ReportViewer.aspx?ReportKey=xxx-xxx-xx-xxx-xx) .User can only see the report not any backen view. But when they use (/dataDashBoards) they able see backend dashborad page as well. Is there any folder/page level access that we are missing or need to configure any additional security mechinism to stop this .

Thanks in advance for all your inputs and direction.

Regards,

Ravi