DIAGNOSIS: The water temperature entering the freezing tray is too warm. This is almost always caused by using room-temperature water in the reservoir for the initial batch.
FIX: For the next batch, use pre-chilled water from the refrigerator. Fill the reservoir with cold tap water and let the machine sit, powered on, for 15 minutes before starting a cycle to allow the water in the tank to cool down.
IF THAT DIDN'T WORK: The ambient room temperature might be too high. These machines work best below 77°F (25°C). Move it away from ovens, direct sunlight, or other heat sources. Ensure there's at least 4 inches of clearance on all sides for airflow.
HEADS UP: Never add salt or any chemicals to the water to try and make it freeze faster. You'll ruin the pump and void any warranty.