SYS_AUTO_SQL_TUNING_TASK fails to run and reports no errors

i have an 11.1.0.7 PSU13 database that is configured to run the Automatic Tuning job every night at midnight and fails to do so.  No errors or attempt to execute are reported in the alert log and the scheduler window shows each night as scheduled.  I have another database configured the same way that does successfully execute the job and reports that in the alert log.  Could someone tell me what dependencies I could check?   dba_autotask_client shows the job as enabled, but no rows appear on the dba_autotask_job_history or dba_advisor_executions tables.

One additional question: The database that is successfully executing this job does so at 2 AM even though it is scheduled for midnight and the tuning window begins at 10 PM.   I have the job scheduled for the local time zone and not GMT.  Any ideas why this would occur?