Sync Contacts
sync macbook pro sierra 10.12.6 contacts with icloud
MacBook Pro, macOS Sierra (10.12.6), sync macbook contacts with icloud
Upgrade your OS - the OS you state you have in one place is (Maverick 10.9.5) which does not support this
In another place you state Sierra 10.12.6 - for it follow these instructions to enable iCloud Get help using iCloud Contacts, Calendars, or Reminders - Apple Support
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