A strange thing has happened on my Nokia Lumia 520. Two of the contacts on my people list had got linked by mistake. I have now unlinked them but strangely messages received from contact x are now showing under contact y. New messages/calls from both contacts are however showing correctly. I tried deleting the two contacts and adding the numbers again but the problem persists. HELP!
I think this is a bug with Windows Phone. Try deleting both contacts, and then re-adding them. I had the same issue once, and it fixed it for me.
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