Some times Mac users faced this issue. Any note created on Mac appears on iPhone and iPad via iCloud. But notes created with iPhone and iPad not appear on Mac.
To sync notes,
If you want to enable notes for your each account, in your iPhone or iPad, go to Settings -> Mail, Contacts, Calenders or Go to Settings -> iCloud.
Go to Settings -> Notes -> Default Account -> ( change this to) iCloud.
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Solution 2 :-
If you want to solve this issue, delete the iCloud account on your iMac and recreate it.
Unselect notes in iCloud preferences. It will delete all local copies of the iCloud notes. Then go to iCloud preferences and select notes again.
In your iOS device, go to System Preferences -> iCloud and un-check Notes Sync. Then logout.
Log in again. Recheck Notes sync and open Notes.
If this method is not working, restart your phone.
In your iPhone 6, go to Settings -> iCloud and turn off Notes. Then turn off phone.
Turn on again. Open Notes app and check notes. None there. That’s good. All notes suppose to be stored in iCloud.
Go to Settings -> iCloud and turn on Notes. Wait a few minutes. Now open notes app. Notes are now synced and updated to Mac and other iOS devices.
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