Instruct: Classify Amazon reviews into positive or negative sentiment
Query: An uncomfortable tub

I first used this tub when my preemie son was just 2 months old. First off, the sling does not snap in place and the head rest is still very hard. Secondly, the sides of the sling are not even padded which may hurt his flailing extremities. He is now 4 months old, and have tried to use it time and again to see if I could eventually like it, and I still don't. I will try again when he's old enough to sit up on his own and see if he likes it.