How can I recover deleted photos from my camera roll?

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If your photos aren't saved in Photo Stream, you need to restore a backup which contains your photos. Go to Settings > General > Reset > Erase All Content and Settings, and set up the phone again. It will ask you to restore an iTunes or iCloud backup, so follow its steps to restore the backup. Finally, you will see the photos on your device.

If you haven't got a backup with these photos and they aren't stored on a computer, you lost them

You can use iPhone Backup Extractor to recover lost iPhone photos, try it yourself, wish it help!

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