Cannot re-download part 1 of 2 part audiobook
I have an iPhone 5 running iOS 8.3. The other day I purchased an Audiobook from iTunes via my iPhone. The book was two parts. The first part downloaded without any problems, but the second part stalled out after starting to download. In my efforts to try and get the second part to download, I inadvertently deleted part 1, which I hadn't finished listening to yet. I have not been able to download part 1 again from my iPhone, nor complete or delete the part 2 download.
I then went into iTunes (v12.1) from my Windows 7 laptop, and search for available downloads and found that only part 2 of the audiobook was available for download, which I downloaded successfully. However, I have found no means of downloading part 1. Anyone have any ideas what I am doing wrong or how to work around this?
Thanks