Embedded Paginated Report - Not full width size

Hi,

we have a paginated report embedded in our page using https://github.com/microsoft/powerbi-client-react/tree/master.

The report has about 15 A4 portrait layout pages and all goes well when exporting to pdf.

The issue is that the visualization in the frame is not right.

The report is not covering all the available frame width. There are always 2 blank columns (right and left). We do not know which parameter to set (if any) so to have the report expanded to use all the frame width. 

Thanks