Based on the screenshot there is an error in establishing the connection to the database or other related to the data retrieval.
Please tes to open the report in the Standalone Designer and delete the SqlDataSorce component. Then add a new SqlDataSource component and configure for use in the report. In case the SqlDataSource uses a stored procedure with schema different than the default one, please test if using the latest internal build, that can be downloaded from Products & Subscriptions - Latest Internal builds - Reporting, resolves the issue. After installing the build, upgrade your project to use it.
If you need further help, please use the support ticketing system and send is a demo report to check its settings and test it locally.
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