The Contacts app uses an intelligent merge feature to combine contact information from various sources (Gmail, Microsoft Exchange, Facebook, new entries, etc.). If contact information was joined in error, the information can be separated back into individual contacts.
From a Home screen, navigate: Apps > Contacts .
Tap a contact to link.
Tap Menu (located in the upper right).
Tap a contact.
If the desired contact is not under the Suggested contacts section, tap Show all contacts.