@Jonathan Thanks for posting in our Q&A.
For "Not checked in" status, it means that the app protection policy isn't applied. To clarify this issue, we appreciate your help to collect some information:
- Please make sure that the app protection policy is applied to a user group and make sure you use the target user to login the Company Portal app.
- Please sync the device and sign out the target user in Outlook. Then use the target user to sign in Outlook again. Check if the "Not checked in" status is changed.
If there is anything update, feel free to let us know.
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