In my list of contacts, I just can't get the integrated twitter ones to show up.
I've synced my account, can view my twitter timeline, have enabled showing twitter contacts under settings>applications>people and still can't get them to show up in my contacts list. So I can't link them to my facebook contacts etc.
Try removing your twitter account and any Twitter apps you have on the phone, and then adding it again to get it re-authorized, all my contacts in all social sites work fine on my Lumia, and Twitter keeps altering OAuth settings , so reinstalling may help !
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