You've received some new phone settings from an unidentified source. If you know the sender and want to accept these changes, ...

You've received some new phone settings from an unidentified source. If you know the sender and want to accept these changes, type the sender's PIN, and then tap Enter. You'll get a text message when the changes are complete.

If you don't want to do this right now, press the Back button to postpone the changes. Tap Cancel to decline them.