iCloud photos and iCloud backup
Iphone 6s Plus with 128 g version 12.0.1
I have iCloud back up with 2 tb of storage. To be safe, Under general tab and iPhone storage, I turned on iCloud photos. This was preparing to switch iPhone. A dial showed 1%. I checked my photos icon and my photos were disappearing. I turned on new phone and connected to icloud. Initiall, it showed all photos, then they all stopped showing. The photos were not deleted. From another iPad device I can view my photos. What can I do to see all of my photos on my iPhone?
iPhone 6s Plus, iOS 12.0.1, 128