Using Outlook for iOS for personal email and calendar management
I understand how concerning this is, especially when important business contacts disappeared immediately after enabling Outlook Contacts.
Please stop making contact or account changes temporarily so the current state is preserved. First, open the iPhone Contacts app and check Lists to determine whether the missing entries belonged to iCloud, Gmail, or Outlook. Then verify them directly through iCloud.com and Google Contacts.
If the contacts were stored in iCloud, you may be able to recover them through iCloud.com > Data Recovery > Restore Contacts. Select an archive from before Outlook Contacts was enabled. Apple states that the current contact version is archived before the selected version is restored.
Please also check Outlook People > Deleted > Recover deleted. If nothing is available and the contacts never appeared in Outlook People, recovery is more likely to be available through the original iCloud or Gmail account rather than Microsoft’s mailbox recovery.
Please feel free to let me know if you have any further updates, thanks.
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