Hello, I'm Joel and will be glad to help you today.
You need to clean the reusable grease filter, follow the instructions below:
click here for instructions
Once you clean that hold the button down for 3 seconds or until the light goes off.
If after that it does not go off, unplug the unit for 5 minutes or kill power to it at the breaker, restore power and try again if it still fails to turn off then the control board has faulted and will have to be replaced.
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