Login again if you wish to continue working.
When you get an ORA-00028 error, make sure to check the alert log and look for any associated trace files.
Due to unknown issue (internal timeout, deadlock, or a bug), the procedure locks itself, and a re-start will usually resolve the ORA-00028 error.
Check with your DBA. Your session may have been killed due to a scheduled outage or other activity.
