What action should be taken if an elevator shows the "out of service" message?

When an elevator displays an "out of service" message, the appropriate action is to report the issue to maintenance personnel. This message indicates that the elevator is not functioning properly and may not be safe to use. Reporting the issue ensures that trained professionals can inspect and resolve the problem, preventing potential hazards for users.

Maintenance personnel possess the expertise and tools necessary to diagnose and fix whatever issue the elevator is facing. Attempting to use or reset the elevator without proper knowledge can lead to dangerous situations, such as getting trapped or exacerbating the mechanical problem. Therefore, immediate communication with the maintenance team is essential for safety and proper functioning of the equipment.