Here are the steps to try to fix a phone that is not saving photos or videos to the camera roll:

1. Check storage: Make sure you have enough storage on your phone and that the photo or video doesn’t exceed the maximum size supported.
2. Restart your device: Force close the camera app and restart your device to see if that fixes the issue.
3. Update the camera app: Check for updates to the camera app through the app store.
4. Check permissions: Go to the settings of your phone and confirm that the camera app has permission to save photos and videos.
5. Try a factory reset: If all else fails, you may need to make a factory reset and set up the device as new.