Instruct: Classify an Amazon review into positive or negative sentiment.
Query: ultrasonic bark controller (NO CONTROL)

I received the product very fast, but it doesn't help quiet or reduce my miniature pinscher bark. He has a very high pitch bark and this product has not been the solution to reduce the barking. I also have a teacup yorkie and it doesn't work on him either. I am very dissapointed.