If you see duplicate contacts after setting up iCloud Contacts
If you set up iCloud Contacts on your Mac or PC and then see duplicate contacts, follow these steps.
Before you begin
If you see duplicates in Contacts on iCloud.com, visit Apple Support for help.
If you see duplicate contacts only on your computer and not on iCloud.com, follow the steps below.
Remove duplicate contacts
Follow the steps for your operating system.
On your Mac
Open Contacts.
From the Card menu, select Card > Look for Duplicates.
When asked, click Merge.
Repeat steps 2 and 3 until no duplicates are found.
On your Windows PC
Visit these Microsoft articles for help:
Information about products not manufactured by Apple, or independent websites not controlled or tested by Apple, is provided without recommendation or endorsement. Apple assumes no responsibility with regard to the selection, performance or use of third-party websites or products. Apple makes no representations regarding third-party website accuracy or reliability. Contact the vendor for additional information.