Usually, you’ll see duplicate contacts when you have the same person saved in multiple accounts, with slightly different info in each one. To fix this, you can link the duplicate contacts. We’ll combine the info from both contacts, and then you’ll only see one with that name. To link contacts:
Open the People app.
Select the contact you want to link, then select the Link button.
Select Choose a contact to link, then pick a contact from your contact list.