rather than changing parameter value you can try to hide the control which you show the parameter value in the report based on the page number.
try to build expression to check current page and set the hidden or visibility property of label/textbox which you have used to show show the details.
RDLC reports you can use Globals.PageNumber to get current page number and also you can set expression as below
How to: Apply Conditional Visibility Controls[
^]