Help recovering my lost files

Hi AbbasMohammadi,

Thanks for coming to Apple Support Communities for help today.

If there is a backup available for you, you should be able to restore it by following the steps found here: Restore your iPhone, iPad, or iPod touch from a backup.

"Restore your device from an iCloud backup

1. Turn on your device. You should see a Hello screen. If you already set up your device, you need to erase all of its content before you can use these steps to restore from your backup.
2. Follow the onscreen setup steps until you reach the Apps & Data screen, then tap Restore from iCloud Backup. 
3. Sign in to iCloud with your Apple ID.
4. Choose a backup. Look at the date and size of each and pick the most relevant. After you choose a backup, the transfer starts. If a message says that a newer version of software is required, follow the onscreen steps to update. If you don't see onscreen steps to help you update, learn what to do.
5. When asked, sign in with your Apple ID to restore your apps and purchases. If you've purchased iTunes or App Store content using multiple Apple IDs, you'll be asked to sign in to each. If you can't remember your password, you can tap Skip this Step and sign in later. You won't be able to use the apps until you sign in with your Apple ID.
6. Stay connected to Wi-Fi and wait for a progress bar to appear and complete. Depending on the size of the backup and the network speed, the progress bar might need a few minutes to an hour to complete. If you disconnect from Wi-Fi too soon, the progress will pause until you reconnect.
7. Now you can finish setup and enjoy your device. Content like your apps, photos, music, and other information will continue to restore in the background for the next several hours or days, depending on the amount of information there is. Try to connect often to Wi-Fi and power to let the process complete."

If it isn't restoring you can check the various scenarios found here and see if they help: If restore from iCloud backup failed

"Learn what to do if you need help restoring an iCloud backup of your iPhone, iPad, or iPod touch.

• Plug your device into power and make sure that you're connected to Wi-Fi. You can't restore from a backup over a cellular Internet connection. 
• Check your software version and update if needed.
• If it's your first time restoring from an iCloud backup, learn what to do. When you choose a backup, you can tap Show All to see all available backups.

The time it takes to restore from a backup depends on the size of your backup and the speed of your Wi-Fi network. If you still need help, check below for your issue or the alert message that you see."

You can also check iCloud.com from a computer's browser to see what information has been synced. Synced data won't be part of a backup and will return when switched on in Settings > [Your Name] > iCloud on your iPhone. This could include Photos, Contacts, Calendars, Notes, etc. You also would not be able to see your device backup here.

If these articles aren't helping, please let us know further details. For example we aren't quite clear how the backup wasn't completed when the iPhone was locked. When an iPhone is locked, connected to Wi-Fi and plugged in would be the exact way an iCloud backup happens overnight.

Have a fantastic day!