Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Poor Quality

I purchased this unit for my newborn son's nursery, to get rid of the smell of his new rug and to protect him against any allergens from our pets. Within only 3 weeks, it flashed an alert to clean the grid and I have cleaned it 3 times and can't get the alert to shut off. Now the smell of the rug is back and the purifier is apparently not working. Because it's been over a month, I can't send the item back to Amazon. Very disappointing - do NOT purchase this expensive product.Meanwhile, the cheapo air purifier we've had in our basement for 4 years is still going strong.