The Archiver hung alerts

select * from V$RECOVERY_FILE_DEST;

SQL> select * from V$FLASH_RECOVERY_AREA_USAGE;

FILE_TYPE PERCENT_SPACE_USED PERCENT_SPACE_RECLAIMABLE NUMBER_OF_FILES
------------ ------------------ ------------------------- ---------------
CONTROLFILE 0 0 0
ONLINELOG 0 0 0
ARCHIVELOG 44.92 0 179
BACKUPPIECE 0 0 0
IMAGECOPY 0 0 0
FLASHBACKLOG 0 0 0

6 rows selected.

ALTER SYSTEM set DB_RECOVERY_FILE_DEST_SIZE = 15G;