Upgrade failed (Unable to purchase the Premium Features)

The "upgrade failed" message usually signifies a temporary App Store glitch and the restore completes successfully when trying at a later time (or after the restart of the device).

Additional steps:
A suggested solution that could fix this is to logout and login on the App Store:

1. Open the App Store
2. Go to the Features page.
3. Scroll all the way down to the bottom and press on the button with your Apple ID.
4. Press log out.
5. Restart your device
6. Once restarted, sign back in to your account.

If that doesn't work please confirm your payment settings on the App Store.

This article from Apple's Support will guide you through the process.
https://support.apple.com/en-us/HT201266

If you are still experiencing any problems, please contact our support team.

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