The Contacts app uses an intelligent merge feature to combine contact info from various sources (GmailTM, Microsoft® Exchange, new entries, etc.). If contact info was joined in error, it can be separated back into individual contacts.
From a Home screen, navigate: Apps > Contacts.
From the Contacts tab (located at the top), tap the Menu icon (located in the upper-right).
Tap Link Contacts.
Select the contacts you wish to link.
Selected when a checkmark is present.