SSRS dynamic parameter value not getting refreshed

Question

We have 3 parameters on the SSRS report:

1. StartDate: Date/Time
2. EndDate: Date/Time
3. DiffDays: Text - Default value based on an expression: =DateDiff(DateInterval.Day,Parameters!Start.Value,Parameters!End.Value)

When the report is previewed, and start date is set to 8th Apr 2019 and the end date is set to 10 Apr 2019, the DiffDays parameter textbox automatically shows 2. However, if either of the dates are changed, then the DiffDays textbox does not get refreshed. For example, changing the end date to 15 Apr 2019, still shows the DiffDays textbox value as 2.

How to refresh the SSRS dynamic parameter value?

Answer 1

In report parameters properties for DiffDays, make available value the same as your default value, and under advanced click automatically determine when to refresh.