SAP B1 - Cancel invoice

Hi,

I just upgraded to SAP B1 9.0, I tried to cancel  a invoice, after I select cancel, and Add it, I realize that I got two invoices, one is closed, other is cancellation, so I think my step is right, but I found the items not back, inventory didn't change,  I mean, the items were included in cancelled invoice not back to warehouse.

who can help...

Thanks a lot

SL