a problem with bookstore

I always have a problem with homeless animals it frustrates me when someone just drops their dog and leaves it abandoned.(ooh), I had new problem with the bookstore just yesterday. I purchased a "required book" for my class and found that the teacher didn't require the book. The book store added the book to the list. The book was purchased last week and it has a 24 hr return policy on the book and now the bookstore will not accecpt it back. Frustrated!!!