Display shows OF OF or O FF; the freezer and fridge are not cooling, but the lights work.

Note: This is not a hardware failure; it is a mode setting.

• Exit demo mode: On most Samsung models, press and hold the Power Freeze and Freezer buttons simultaneously for 3–5 seconds until a chime sounds and the display changes. On some models, use Power Freeze + Power Cool.
• Verify cooling: After exiting demo mode, allow 4–6 hours for the freezer to reach the set temperature.
• Power reset if needed: If the unit will not exit demo mode, unplug for 5 minutes and try the button sequence again.