Can you help us understand? For instance, "seems to have ample storage" isn't very specific. Can you tell us what is your storage is on this iPhone? At Settings>General>iPhone Storage, my phone says 50.5 GB of 128 GB used. What does yours say?
First, try a forced restart:
Force restart iPhone - Apple Support
This is different from a simple Power Off. For me, the logo appears 5 or 10 seconds past the "slide to power off" message. Wait for the logo; don't do the slide thing.
Also,
- What iOS does your phone use?
- Are you using iCloud Photos to synchronize your devices? If so
- …Do you have “Optimize Storage” checked in Settings>[name]>iCloud>Photos>
- …Do you see all your iPhone pictures at iCloud.com?
- …What is your storage in iCloud? At Settings>[name]>iCloud>Storage, mine says 166.6 GB of 200 GB used. What does yours say?
- At Settings>Battery, what do Battery Health, Maximum Capacity, and Cycle Count say?
Can you tell us what your phone says about your Photos Library? Look in Collections:
