Hello Jeff,
Welcome to Microsoft Community and appreciate your time taken for sharing detailed information. I could share with you some of my thoughts on this issue.
There are three situations that can cause duplicate contacts on your iPhone.
- iCloud Problem
Due to iCloud server issues, iCloud may copy your contacts. So, just log in to your iCloud account and see if there are duplicate contacts. If so, you will have to contact Apple support to resolve the issue.
- Microsoft Exchange Servers Issues
iCloud doesn't change the data that syncs with Microsoft Exchange servers. So, you may find yourself having duplicate contacts on your iPhone. Unless you set one of them to sync with your iPhone, the chances of repeating your contacts are high.
- Syncing both iTunes and iCloud
If your device is set up to sync with both iTunes and iCloud, the issue of duplicate contacts can occur. This problem is only possible if you are using versions of iTunes before iTunes 11. The solution here is simple, just upgrade your iTunes to the latest version.
Judging from your description, it is very likely that the first two situations are causing your problem. If you want to fix this, you may need to go to groups and then just select a feed to sync your contacts. (Click Contacts > Groups > Select one of the contact source options given: “All iCloud,” and “All Exchange/O365”.)
Feel free to post back if you need any further assistance.
Best Regard,
Kevin | Microsoft Community Support Specialist
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