The appliance turns on but does not release steam.

You need to check the position of the float. This is a moving part that may look like a white, hollow cylinder, located in the base of the device or under the tank. This float has a built-in magnet that indicates to your device if there is water in it. If the device does not detect water, it stops so as not to damage the ultrasonic plate. You need to check that the tank float is moving (not stuck). You can also clean this part with white vinegar.