PBI Report Server - Export Data issue

Hi 

Im experiencing a strange bug with the power bi reports in the report server.

My report has connected to SSAS using live connection and for some visual I can export but for some like bar charts and matrix, i can't basically just doesn't do anything.

Tested publishing the same report to PBI cloud and exporting with summarised data in excel works perfectly fine.

In the report server, what does it do when I click export data ? 

Does it export the summarised or underlying data ? Is there any way to change so it can export the data as excel and summarised data instead of underlying data  ?