I am experiencing a problem with intermediate catch event.

If I add a intermediate catch event (say signal event) to a process,

the process will process to the task following the signal event (eg. Close Up).
my process

The associated work item handler runs all right, but the process just won't complete.
What I mean by "it won't complete" is that process's status is still 1 (active) and the session is not deleted when I look at processinstancelog and sessionifo table in database.
processinstancelog table
sessioninfo table

How do I turn a process instance into complete state after signalEvent?