RMAN-03002: ORA-19693: backup piece already included

I have been cursed trying to create 25TB standby database.

Active duplication using standby as source failed due to bug.

Backup based duplication using standby as source failed due to bug again.

Now performing traditional restore.

Both attempts failed with RMAN-20261: ambiguous backup piece handle

RMAN> list backuppiece '/bkup/ovtdkik0_1_1.bkp';
RMAN> change backuppiece '/bkup/ovtdkik0_1_1.bkp' uncatalog;

What’s in the backup?

RMAN> spool log to /tmp/list.log
RMAN> list backup;
RMAN> exit

There are 2 identical backuppiece and don’t know how this could have happened.

$ grep ovtdkik0_1_1 /tmp/list.log
    201792  1   AVAILABLE   /bkup/ovtdkik0_1_1.bkp
    202262  1   AVAILABLE   /bkup/ovtdkik0_1_1.bkp

RMAN> delete backuppiece 202262;

Restart restore and is running again.