SP2-0618 and SP2-0611
An user reported errors SP2-0618 and SP2-0611 when he tried to enable AUTOTRACE at his session-time.
SQL> show user
USER is "HR"
SQL> set autotrace on;
SP2-0618: Cannot find the Session Identifier. Check PLUSTRACE role is enabled
SP2-0611: Error enabling STATISTICS report
SP2-0618 and SP2-0611 means that the feature you want to enable has no table to store statistics, furthermore, you have no right to do it.
To solve the problem, we should grant role PLUSTRACE to the user to make it privileged, then tell the user to reconnect to the database. Please check the post: How to Enable AUTOTRACE for more details.