Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Design Flaw

The heat sensor next to the lamp appears to be set at the wrong temperature. The lamp turns off after only about 7 - 10 minutes of use, waits for three minutes, and then turns on again for another 7 minutes or so. This has happened on both the original model we ordered early in 2011, and now it is happening with its replacement. We checked to make sure the air vents were uncovered and the lamp was properly seated.