I have iCloud photo library enabled. Everything is uploaded to iCloud via my iMac and I use Photos app. However on my iPhone, all up to date, loads of photos show a white circle with a ! inside. This is on 4G and WiFi at home. It sits there won't do anything. I'm worried why they wont. I've restarted, airplane on/off, WiFi on/off. I don't really want to have to turn off iCloud photo library on my iPhone if possible, I had to in the past for a different problem and it took ages to get all pics on again. Anyone help? They seem to be there on the iMac?