Sprint Planning Table

I figured out that part of the problem is that the next sprint member is not necessarily the next upcoming sprint that I have. I’m trying to use the example from the EasyBi demo set to create a calculated Sprint Member that is ordered by title

Aggregate(
Order(
[Sprint].[Sprint].Members,
Val(ExtractString([Sprint].CurrentMember.Name, ‘.* (\d+).*’, 1)), BASC
)
)

But I get this error when I try to select it

Any suggestions here?