RMAN-06059 expected archived log not found, loss of archived log compromises recoverability
Cause: The archived log was not found. The repository thinks it does exist. If the archived log has in fact been lost and there is no backup, then the database is no longer recoverable across the point in time covered by the archived log.
This may occur because the archived log was removed by an outside utility without updating the repository.
Action: If the archived log has been removed with an outside utility and the archivelog has already been backed up, then you can synchronize the repository by running CROSSCHECK ARCHIVELOG ALL
rman target / nocatalog
RMAN> crosscheck archivelog all;
RMAN> delete expired archivelog all;
then re-run RMAN backup command....