Missing Lower Lvl Categories when filtering Upper Lvl Categories in a Dimension

[kgcognos]

Iam using a cube dimension containing Customer Class and Customer.
Using Report Studio, I have a value prompt for the Customer Class.
Then my cross tab contains Customer as rows and Fiscal Year as columns. Sales $ as measures.

When I first run the report, it shows all Customers. But when I filter on Customer Class, not all members for that class is showing up.

In my Detail Filter I have this
[Sales Cube].[Customers].[Customers].[Customer Class Code] in ?pCustomerClass?

How do I fix to show all members based on the Customer Class parameter?

Thank you in advance.

[Lynn]

You should not be using detail filters if your source is a cube. Try using a context filter, or a filter function on your customer class set, or create an expression to nest on one of the edges as

[Sales Cube].[Customers].[Customers].[Customer Class Code] -> ?pCustomerClass?

[kgcognos]

Thank you. I used the slicer and it works
set([Sales Cube].[Customers].[Customers].[Customer Class Code] -> ?pCustomerClass?)

But now my Customer Class prompt is required. How can I make that optional?

[Lynn]

You can use a prompt macro and set a default value as the root member.