Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Not working for us anymore

My cat has been eating this brand for about a year with no issues. Ever since they changed the kibble shape, my cat has been vomiting after his meals. I'm guessing they must have changed more than just the kibble shape because something is not agreeing with him. I have been trying to figure out what else could be the issue. He is very healthy and I see no other changes in him. He is still his very energetic self which makes me think no health issues are to blame. I've changed his food and so for no vomiting.