Rental movie "waiting to download"

I rented two movies last night, the second one before the first one finished downloading. I understand that AppleTV will always finish downloading the most recently rented movie first so that's fine. I watched the second one and hours later, the first one still says "Waiting to be downloaded". I clicked the movie and pressed "Start Downloading" but nothing happened. I went to Settings and Downloads and all it showed was that it was waiting to download and it has only downloaded 24%. No matter what I press, it won't get it to continue. Does anyone have any suggestions?