As a last resort, you can sign out of iCloud and log back in. On iPhone/iPad, go to Settings > [Your Name], scroll down, and tap Sign Out. On Mac, go to System Settings > Apple ID > Overview > Sign ...
iCloud Photos provides a convenient way to backup pictures and access them across your Apple devices. A feature of iCloud, Apple's cloud storage service can also be used to backup your iPhone and iPad ...
iCloud Photos lets you see the same images and videos on all your devices connected to the same iCloud account and with syncing for Photos enabled. If you aren’t seeing synced media, or your media isn ...