Diagnosis
You cannot cancel a billing document if its current status is Beingtransferred or Already cancelled.

System Response
The system does not cancel the billing document.

Procedure
If the status of the billing document is Being transferred, waituntil you receive confirmation from Accounting that the transfer iscomplete, and then cancel the billing document.
If the status of the billing document is Already cancelled, thenthis billing document has - as the status suggests - already beencancelled.