Hi @Raheem Anderson ,
Under normal circumstances, this will only happen if the Azure AD user is deleted.
1.Please check M365 Admin center, whether the account is in Active Users or Deleted Users.
2.Have you checked whether the user has been deleted through the Audit log? If not, you can check to see if there is a delete record.
Go to https://compliance.microsoft.com and sign in. In the left pane of the compliance portal, select Audit.
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Hi @Raheem Anderson ,
Would you please provide us with an update on the status of your issue?
Hi @Haoyan Xue_MSFT
Sorry for the late response. I was waiting for feedback from the user.
The user confirmed that SharePoint access they had from other users onedrive/emails that left the company more than 90 days were inaccessible. Could this be cause of the received email?