Blank Pages Issue When Hiding Rows Based on Parameter Value in Power BI Report Builder

Hi,choime .I am glad to help you.

The general cause of blank pages is related to the layout settings of the report, although the sub-report has been hidden by the parameter, but you mentioned that you set the paginated reports, which may cause the report to unexpectedly appear blank pages after printing.
Your current problem is that when the actual content is just about ready to be displayed on the same page of the paginated reports, there is still content that cannot be displayed properly, so this part is displayed on the next page, but in the actual printing process, this part is displayed as blank, so there is a blank page. When the content of the main table is displayed as two pages, the size of the two pages is just enough to display all the contents of the paginated reports, so the normal display of reports.

You may need to double check the layout settings, hopefully the link below will help:

URL:
Avoid blank pages when printing paginated reports - Power BI | Microsoft Learn
Solved: Power BI Report Builder paginated report page brea... - Microsoft Fabric Community
 I'll follow up with the relevant tests to try to reproduce your problem.

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Carson Jian,
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