I created simple custom workflow (Start -> Notification -> End).
I got the following error when I run the workflow.
[WF_ERROR] ERROR_MESSAGE=ORA-02289: sequence does not exist ERROR_STACK= FND_SEARCH_EVENTS.On_Object_Change(oracle.apps.wf.notification.send, 5C84790B967158FFE04400144F23BF3C)
The notification activity returned this error but the notification has been sent to performer.
I searched for solution to fix this problem and I found one result for the same problem without any solution.