Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Worked great!!! ...for three days

The first night I used this humidifier, I thought it was great! It was very quiet and seemed to do the job well. After only three uses, however, I have noticed that it stops emitting mist after about an hour, but the fan continues to run. The water in the base is warm, indicating that the motor is overheating. I plan on trying to return it today.