iOS 10 face recognition - how to reset the list of detected people?
I found some errors in the list of detected people, wrong names attributed to photos. How can I reset the face recognition on my photo stream?
Solution 1:
So this may not be a way of resetting all face entries at once, but you can do them individually by selecting all of the photos in each entry, hit the share button, then press "Not This Person". The entry will disappear and the photos will go back in to the untagged pool.
Source: How to unconfirm faces in iOS 10?