ORA-12012 ORA-27468: "SYS.PURGE_LOG" is Locked by Another Process ORA-29516: Aurora assertion failure

SQL> STARTUP UPGRADE
SQL> SPOOL patch.log
SQL> @?/rdbms/admin/catupgrd.sql
SQL> SPOOL OFF
SQL> SHUTDOWN IMMEDIATE
SQL> STARTUP
SQL> @?/rdbms/admin/utlrp.sql