Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Defective out-of-the-box, poor response from Munchkins

We purchased two of these cups from a retail store. The straw assembly in one of the cups was defective from the start even though we "activated" the straw. Neither my toddler nor I could get liquid up.We contacted the manufacturer and finally got a response -- ONE MONTH later!!! The response was not helpful, explaining that our problem was caused by incorrect use. They eventually sent us a pair of replacement straws THREE+ MONTHS after our first e-mail. (FYI -- One of the two straws arrived defective.)The second cup worked well for a little while. As mentioned by another reviewer, the straws do not last. After limited use, the one "good" straw sprung a leak.