Reviews for defective items

I know this question has been asked before, but I can't find a thread with the exact information I'm looking for. I got my first free toy to review in the mail today but it doesn't seem to be working properly--it turns on, but it's temperamental and doesn't seem to have all of the functions it's supposed to. So, first of all, am I correct in assuming that this is the kind of thing that should be returned rather than reviewed? And if so, who exactly do I contact to say that I won't be able to review it? less