Beware of the nook book ParaNorman. The webpage says FREE in massive orange letters and below that says $0.00. However if you press buy, like I did, you'll get charged $6.99 + tax. Meh.
So call CS talk to tHem. You have the screen capture and most likely the email with the charge. Btw, the free version is only a preview. There are two versions out there, it looks a mistake and this pointing to the wrong version. When you clicked on buy now, did you get a popup window that daid your card would be charged? In any event, I'd call CS.
I've had this problem in the past with books that have 2 nook book versions listed. I avoid buying from such a listing. It appear the B&N site has problems handling this. Call CS, I did and I got a refund.