Photos won't upload from iPhoto album correctly
When I upload an album from iPhotos to iCloud or Photobox, the photos import out of sequence, there are some missing photos and some photos appear that are not saved in the album. I am trying to make a photo book but it's impossible with the album not importing correctly. I haven't had this problem before but haven't tried since I got this new MacBook. I am using Mac OS Catalina on a 2019 13" MacBook Pro. Any help would be welcomed.
MacBook Pro 13", macOS 10.14