I got a new Mac recently and decided to set up my iTunes account. I signed in with my Apple ID and plugged in the iPhone to transfer purchases from the iPhone to iTunes. When I try to do so, it says nothing can be transferred because I "am not authorized for them on this computer." So I hit "Store" and "Authorize this computer" as it told me to, and it tells me the computer is already authorized! It's an endless cycle of this over and over again. What am I to do?