itunes not synced

Trying to get my ibooks from my Mac to my iphone but i get this: the iphone could not be synced cuz this computer is no longer authorized for purchased items that are on this iphone.

The icloud account on my mac is the same as on my iphone.

I deauthorized my itunes account and reeauthorized it. Nothing improved.

I keep getting the same notification that the account is not authorized.....😠 annyoing!

All I want is my iphone and my mac to be properly synced