Error: the Fast Recovery Area (FRA) is full due to the presence of a guaranteed restore point, which prevents flashback logs from being reused or deleted.

Solution:

Check Existing Restore Points

SELECT NAME, GUARANTEE_FLASHBACK_DATABASE, SCN, TIME FROM V$RESTORE_POINT;

Drop Unneeded Guaranteed Restore Points

DROP RESTORE POINT restore_point_name;

Disable Flashback Database

select flashback_on from v$database;

-- Disable
ALTER DATABASE FLASHBACK OFF;

Manually Delete Archive Logs (If Needed)

RMAN> DELETE ARCHIVELOG ALL COMPLETED BEFORE 'SYSDATE-1';

Increase FRA Size (If Space Is Still Tight)

ALTER SYSTEM SET DB_RECOVERY_FILE_DEST_SIZE = 50G;