MMMageshyadav M Syncfusion Team January 8, 2019 07:27 AM UTC
Thanks for your interest in our Syncfusion products.
In Syncfusion Report Viewer, white spaces will be preserved in the report body by default. When the white space extends the body size or beyond the width of the report during design then that extra spaces will be loaded in report preview. So can you please adjust your margins, page width and body width as shown in below snap to avoid the mentioned extra spaces issue at your end.
Page Width and Margin:
Please find the below documentation link for your reference.