Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Not happy

This collar worked for about 4 months and then stopped working. Fortunately I still have the original packing and proof of purchase. However, the Pet Smart Store would not give me an exchange or refund my money for the defective collar. They said I had to contact the manufacture, Radio Systems. After a lengthy phone conversation with Radio Systems customer service, they agreed to send me a new color for $18.00 and I promised to send the defective collar back to them. RS will not refund the cost to ship their defective product back to them. The cost to send the defective collar back is my cost.Radio Systems charged me $40 not $18 for the replacement collar. So now I have to have another long conversation to get my refund. I am not happy with the product, and not happy with their warranty service. I would not recommend this product.