iTunes albums missing on iPhone

[allan53]

I had not sync photos from my hard drive to my iPhone and iPad for quite a while - I added a few photos to my "photos for devices" folder on an external hard drive. Inside the folder there are about 50 subfolders and perhaps 1900 images. These subfolders have always shown up as albums under My Albums" on my iOS devices when the photos were synced. However, when I synced today, though the 1900 are on my iPhone, the section under "My Albums" is blank.
I was afraid to sync the iPad so it is still correct.
iTunes 12.6.1 IOS and Mac OS latest versions 10.3.2 and 10.12.5

Here is the way it is on my iPad and the way it had been on my iPhone

Here is the way it is on the iPhone after the sync