If you have outlook contacts saved onto your iPhone, make sure to import these contact BEFORE removing the account from the settings

Settings > Contacts > Import Contacts > Select Email account.



Once Outlook is configured, Follow the steps below to re-sync Outlook contacts on IOS:


1. Open Outlook on your iPhone.

2. Tap on your user profile image on the Top-Left.

3. Tap the Cogwheel on the Bottom-Left.

4. This will being you to the app settings, Tap on your Office 365 Account.

5. Turn on the Option for save Contacts.