Hello dear iPhone Help community. I own a iPhone 6 and I'm the first owner of the device. Before a week I created a backup via iTunes, and today I restored my phone with the new iOS version. Now when I tried to restore my iPhone from the created backup, I got a popup message: Enter the Password to Unlock your iPhone Backup asking for backup password.
Here's What I tried:
- I entered my Apple ID password, but it was not accepted.
- Tried backup extractor, but still ask for password.
- Disabled the encrypted backup from the settings.
Here's the screenshot from the iTunes error page:

Can you help me to fix this problem? I don't want to lose my data. I have very important data in the backup file.
Thanks,
Stephan.