What should I do if the heater doesn't work even though all switches are on and thermostat is set to the highest level?
The thermal protector has likely tripped. Turn all switches to the "OFF" position and unplug the unit from the wall outlet for 5 minutes. After 5 minutes, plug the unit back into the wall outlet and operate as normal.
From the official Duraflame Space Heater with Flame Effect manual, page 2
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