Hello,
Thank you for posting in Q&A forum.
Based on your description, we recommend that you try the following methods to solve the problem:
Ask users to check the room calendar to see if there are any other booking conflicts. Users can try changing the booking time or selecting another meeting room.
Ensure that the user's Outlook client is properly synchronized with the Exchange server. If you suspect a sync issue, you can try restarting Outlook or reconfiguring your account.
Verify that the user has the correct permissions to view and book the room. Administrators can check and modify permission settings in the Exchange admin center or Outlook Web Access.
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best regards,
Jill Zhou
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