Bencao disappeared off of my wife's new iPhone 7 – Bencao: Chinese Medicine Herbs Review

My wife and I both have Bencao on our iPhone's for many years and we use it all of the time. We both just got iphone 7 and we restored them from our last backup of our 6S. My Bencao was on my new phone but it was not on my wife's iPhone. She went to the App Store and it was only for purchase but she already purchased it years ago. Can you please advise how to restore Bencao on her iPhone.
Review by Taijitom on Bencao: Chinese Medicine Herbs.