Julie,
1. Please paste the screenshot of billing document 933024130 with FKSTO
(in a previous post, you have given the Posting status = E for this billing document but what about FKSTO)
2. In VF03 put this billing document and click on document flow. Paste that too.
3. To cancel a billing document, another (cancellation) billing document is created. So if 933024130 is cancelled then there should be another billing doc after this. Would you agree?
4. In VF02, give 933024130 and try to release it (Green Flag). What message are you getting?
Thanks!