Quote Originally Posted by habeebksa
On month end I delete the archive logs from rman by giving the command to remove the previous one month old archivelogs from the disk.

RMAN>delete archivelog until time 'sysdate-30';
This is only deleting your archivelogs and NOT your backupsets. How are you actually deleting your backupsets?

I know this may be an obvious question, but have you verified that the backupset exists on disk/tape?