[otrs] Can't seem to close a ticket

OTRS v2.3.2. I have a ticket, created by using the 'Email-Ticket' to Compose Email/ new ticket. Addressed from a specific queue to keep track of it. Now I cannot close it. The close generates mail that is sent to the email address of the queue and opens it again. How can I close it and how can I avoid this state in the future? Is there some misconfiguration issue? This doesn't seem to happen in the Phone-Ticket. - Sarah Baker Dir of Ops, mSpot Inc. 650-321-7000