Instruct: Classify Amazon reviews into positive or negative sentiment
Query: It didn't do what it was supposed to do.

As a beauty and fashion professional, and I was totally disappointed with this product. I followed the directions closely. My hair got straight after applying the treatment and flat iron. It stayed sort of straight during the 2 or 3 days i was supposed to leave. But when I washed it out, regardless of how much i flat ironed it, it didn't stay straight for more than a day. If I have a busy day, i had to flat iron my hair 2 times a day.My advice, spend the money, DO YOUR RESEARCH and buy a better product.