There is not always someone on duty in a department. The worker on duty was serving someone, and I waited patiently. The staff is busy so I walked away from the isle briefly. After I returned the staff disappeared and I waited for 15 minutes and no one appear. I checked isle to isle and did not see anyone. Asked someone else whom does not work in the department for assistance. The person was helpful. But that staff whom is on duty is really not responsible.