When you open any saved Power BI workbook and see the following error, don't worry, it is simple to fix.
It could be due to following reasons:
1. You have created and saved a workbook using a report in OBIEE (Ex: Report1).And suppose that report was renamed or removed from OBIEE after saving the workbook. Now if that workbook is opened, OBIEE will search for the report with old name(Report1) and hence returns error. So, you can verify if that report exists in OBIEE or not.
2. Another possible root cause for this error is, if new report is created in OBIEE but you haven’t preloaded (“Preload Metadata”) after that. The newly created report doesn’t exist in your local BI Connector cache. So BI Connector consider that the report doesn’t exist in OBIEE and returns error. To resolve this error, you should click on “Preload Metadata” button in BI Connector. Refer this article for How to use Preload Metadata option in BI Connector?