Hi
Based on my search, I do not find the document list the data model limitation in Power BI desktop. But there is a limitation in Power Query: Maximum number of rows filled to worksheet is 1,048,576. As Power BI will generate backend query when we get data, I guess the issue might be the number of rows exceeds the Power Query allowed rows.
In your scenario, please get data from the same SSAS data source under Power Query tab in Excel, check if the same issue occurs.
Best Regards,
Qiuyun Yu