Find "Edit"
Press the menu icon.
Press People.
Press the second tab.
Press the required contact.
Press the settings icon.
Press Edit.
Merge identical contacts
Press the settings icon.
Press Join.
If no suggestions are displayed:
Press Show all contacts.
Press Show all contacts.
Press the required contact.
Repeat this step to merge more contacts.
Repeat this step to merge more contacts.
Exit
Press the home icon to return to standby mode.