Book Will Not Download

I have an iPhone 6 Plus running iOS 8.3. I'm trying to download a book that I previously purchased and had on a previous iPhone. I've tried 3 different ways to get the book to download into the phone but it just goes back to showing the cover with the "download cloud" in the upper right corner?

1st Method:

I open iBooks and find the book and tap the "download cloud" and it looks like the book is downloading - the blue line appears at the bottom of the cover and fills from left to right but then comes back to the original cover with the grey "dowload cloud" in the upper right corner. This happens whether I'm using wifi or ATT 4G Lite.

2nd Method:

I open iBooks and press the Purchased icon at the bottom. On wifi or 4G Lite, "downloading" begins but then I'm back to the download cloud icon.

3rd Method:

I went into iTunes and found the book and clicked on the "download cloud" icon on wifi or ATT 4G Lite and it only cycles back to the original download cloud icon.

What do I need to do to get this book and other previous purchases to download into this phone???

Thank you