stop auto syncing numbers to facebook

I'm helping my wife set up her iPhone 5.

She does not want to sync her Facebook contacts to her iPhone contacts. I have turned off contacts in the Facebook settings on the iPhone. Her Facebook friends are not showing up in her contacts.

Here is the problem. When she receives a call from someone she has not yet added into her contacts and tries to save the number, the number is automatically synced to the Facebook information for that person. Since the Facebook contacts are turned off, that contact then does not show up in the contacts on her iPhone.

Can anyone help with this? It's fairly annoying.

Thanks.