44 pages of people with the same issue. I think Apple needs to investigate this and solve it.
I have been fighting this issue since my iPhone 4.
I found that Apple automatically creates albums from your pictures you upload to the iPhone: The automatically created albums include (but this may be an incomplete list): People, Places, Videos, Selfies, Live Photos, Portrait and Panoramas.
Once these albums get created, you can't delete the picture from the album it came from and have it get removed from this automatically created album!.
I've gone so far as delete ALL my pictures (over 50,000) and then see that the automatically generated albums are still there WITH THE PICTURES still in them even though they have been removed from the iPhone! At that point it becomes obvious: You can't add ANY new pictures back onto the iPhone (even the ones you just removed!) and you can't get rid of the automatically generated albums UNLESS YOU RESET YOUR IPHONE!
I kept a backup of my iPhone just to the point before I added ANY pictures and can restore to that point and then add the pictures again.
Apple has 2 methods they describe to add pictures to the Photos app on the iPhone:
1) Use the Photos app on the Mac (assuming you HAVE a Mac, which I do) OR
2) Have a folder on your Mac (in my case called Pictures) and when running iTunes point to that folder and EITHER:
2a) Select All Folders
or
2B) Select the folders you want to add individually from the list of folders that shows up and is created by iTunes and maintained in the iPod Photo Cache inside your folder (mine is, again, Pictures)
If you use the Photos app, you must create the albums you want to be on the iPhone one at a time. this takes multiple steps for each album. Once done, though, it seems to upload to the iPhone with little issue.
If you select the All Folders or individual Folders, it DOES get done BUT here is where the Software does not work anymore. It won't let you update any of the pictures in any of the folders (inside Pictures) or even add a new folder (in Pictures). Weirdly, any new folder DOES show up as a new Album, but no Pictures that are in the Folder get put onto the iPhone in that new Album.
I determine from this scenario, having written lots of software in the past, the software that creates those automatic generated folders DOES NOT CHECK them to see if the pictures are on the iPhone at each sync. That is what it SHOULD DO.
If I delete all the "Live" photos from my folders in Pictures on my Mac, for example, then iTunes should be removing them from the "Live" folder it creates and if they have all been removed from my folder (Pictures) on my Mac, the automatically created folder should disappear.
APPLE - fix the software.