Dimension invalid for a selection (BEx Query)?

Hi All

I am quite new on SAP BI/BW.

I have a BEx Query on top of the standard IC 0FIGL_V10, everything looks fine.

Then I copied the IC to ZFIGL_V10 (changed the underlying function module) and kept everything same. I created a new Query on top of it, for Rows I created a Structure, and then a Selection under it.

I try to use the members under dimension Accounts for this Selection, but Query Designer only allows me to use member Ledger (there are 4 members totally).

I can not find any difference between those stuffs, and everything is OK for the standard IC.

What could be the issue?

Thanks in advance.