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Sign into your new phone with the same Apple ID you logged into your old phone.
Verify that your contacts have synced to iCloud.
Enable syncing on your new Phone.
Log into iCloud to Verify your Contacts are Synced
In a browser, go to www.icloud.com and log in with your Apple ID and password.
Click Contacts. You should see all the contacts that are on your current (old) iPhone. The same applies to Notes, Reminders, and Photos.
On your new iPhone, tap Settings.
Tap your iCloud account.
Tap iCloud
Make sure Contacts, Reminders, and Notes are turned on, so these items sync.
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