IOS 6 on iPhone 4.
I enabled Facebook integration and it correctly associated many contacts in the address book with Facebook friends. There were some errors (a contact got linked to a person I don't know which not only is not on my friend list, but with which I never even exchanged a single message), but I corrected them manually.
Now, sometimes a person will not use his/her real name on Facebook, or maybe will put a nickname as middle name. Or maybe I decided to label the contact in some different way than the person's real name. Anyway, the point is: sometimes, address book names and Facebook names differs. In all these cases, when the iPhone linked a contact with a Facebook friend, or when I manually linked them, it always displayed the names from Facebook instead of the ones I had been using in the address book. I corrected this, too.
But, here's the problem: when I make such a correction, looks like it works... but then, after a while (even 1-2 days), it reverts back to using the Facebook names instead of the ones I put in.
Is there any way to permanently tell the iPhone "I want this contact to be called such-and-such and please don't mess with it"?