iphone pro 14 with iOS 16 not automatically backing up over cellular

icloud backup and backup over cellular are enabled. I have unlimited 5G cellular data and no WiFi access. I put the iPhone on a wireless charger every night.

Why won't the iphone 14 with iOS 16 automatically back over cellular? I keep getting a notification every 2 weeks "your device hasn't been backed up..." and I have to manually tell it to back up and each time I have to answer "yes, use my cellular data for backup"

Why won't photos backup over cellular unless I put the iphone on a charger and manually open the photos app and swipe up when viewing my library?