Hi Seema
You are correct. OSS Note 1259505 mentions the various reasons in which the new clearing functionality will work and when the clearing will not work.
Some of the common reasons, why the clearing will NOT work:
1. You have an excise invoice (CIN) created for the SD invoice
2. You have an user exit in COPA for derivation and the values in derivation have changed between invoicing and cancellation
Also refer the below links for help:
How to analyze SD Billing New Cancellation Failure - ERP Operations - SCN Wiki
FAQ in Billing Cancellation - ERP SD - SCN Wiki
Thanks & Regards
Sanil Bhandari