When Scheduling a Bursting Report, the Parameters in trigger are Not Loading on the Schedule Tab

I have a BI Publisher data model that accepts a :from_date parameter and includes bursting logic.

To handle the "no data found" scenario during bursting, I created a trigger that should execute and skip the bursting when no data is returned. However, when scheduling the report and selecting the trigger, the :from_date parameter is not showing or populating as expected.

In the below image, exactly below the Trigger selection area , The parameter value is not populating in parameter section

I need help understanding why the parameter is not recognized in the trigger during scheduling.