I cannot access all my photos from the cloud on my iPhone 6
I uploaded all my photos to the cloud anticipating I would have all my photos accessible from all my devices. If I am home, in front of my Mac, all photos appear on my iPhone 6. Earlier today, away from my home and Mac, I wanted to show someone a special photo and could not access it. There were lots of blank spaces that contained a little white cloud in the corner but no photo. I do have iCloud set to use Cellular Data when not connected to Wi-Fi. What can be the problem?
iPhone 6, iOS 9.3.3