Thank you for asking this question on the Microsoft Q&A Platform.
I understand that you have a user with a synchronization error.
The user has a different Object GUID, but te have the same value UserPrincipalName When I have this kind of issue, I do a hard match user account (More info https://messageops.com/step-by-step-guide-to-hard-match-a-user-on-office-365-or-azure-ad/https://www.smikar.com/azure-ad-hard-match-user-accounts/ ) Hope this helps!
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