Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Arrived Defective

We had great hopes for this collar for our constantly barking boxer. It did not work at all! The battery is fine, as we can rub it against a VERY rough surface and it will beep and work but it does not respond to our dog's bark at all. It is no where near sensitive enough. Given the other reviews, I think it must be defective and we are contacting the company for a replacement.