CAUSEThis is expected behavior due to cancellation of one of the Auto Tuning jobs. A second job is spawned for the same task and ORA-13629 exception can be encountered by the database.
There may be 2 jobs running for the same Auto Tuning tasks "SYS"."ORA$AT_SQ_SQL_SW_408".
The auto sql tuning task may be interrupted or canceled for some underlying reason, and hence the exception of ORA-13629 was raised. The underlying reason of interruption is not known, but most likely it is outside the database.
SOLUTIONThe error can be safely ignored and is harmless. This is considered normal behavior due to cancellation of one of the Auto Tuning jobs.
Check the property of the advisor to see whether it has been execute multiple times.
If it is the case, create a new execution or resume the last task execution, but only if the task is not currently being executed.