Read help info
If the same contact appears more than once in your phone's address book, you can merge identical contacts so that they will appear only once.
1. Find "Contacts"
Slide your finger upwards starting from the bottom of the screen.
2. Merge identical contacts
Press and hold the required contact to select it.
Press the required contact.
Press the menu icon.
3. Return to the home screen
Press the Home key to return to the home screen.