DIAGNOSIS The water pump is likely air-locked or the water inlet tube inside is kinked/blocked. This stops water from reaching the freezing tray.
FIX Turn the unit off. Remove the water reservoir. Tilt the entire ice maker forward over a sink to drain any water from the internal tank and lines. Reinstall the reservoir, fill with fresh water, and restart. This often clears the air lock.
IF THAT DIDN'T WORK Check the small silicone inlet tube that runs from the reservoir slot to the pump. Make sure it's not pinched or folded over when the reservoir is inserted.
HEADS UP Always use the unit on a hard, level surface. On a soft or uneven counter, the internal alignment can shift, kinking that tube.