In several cases that have been reported to the Microsoft Lync Online services, we are seeing customers reporting that they are unable to view presence information correctly inside their OWA environments.
One possible reason for this could be that you are experiencing a UPN/SIP mismatch. The steps below will perform the UPN swap.
1. Log into Microsoft Online Portal (portal.microsoftonline.com) with admin credentials
2. Go to the Users page under management and click on the user in question.
3. Go to the Details page for this user and change their domain to the .onmicrosoft.com domain and click save.
4. Allow 30 minutes for propagation then have the user log into the Microsoft Online Portal.
5. Return to the Details page for the user and change their domain back to what it needs to be and save it.
6. Allow up to 30 minutes and try to log into Lync.
Although 30mins above, please allow enough time for the changes to take effect which should reset the primary attributes fix other field issues and get these accounts showing correctly.