Instruct: Classify Amazon reviews into positive or negative sentiment
Query: waste of money but amazon is great

Despite the positive reviews, this air bed didn't even last one night. The inner chamber was leaking and I could hear air seeping out through the built-in pump. I followed the inflation instructions completely, but unfortunately nothing worked out for me. This was a waste of time purchase - however, Amazon is great. Because I wanted to return the mattress within a month of purchasing it, I was able to get a refund through Amazon.