Hello,
I think you should do update your product key. Try this steps.
Open Fences 5 Configuration Windows-> Click on About tab-> Click on Manage product key-> Click on Update Product key-> Once you select that. A new activation windows popup. You should enter your ObjectDesktop license key in there. That should do it.

Also, you can use this guide to review your activation and delete old activation: https://forums.stardock.com/486311/accounts-and-activation-support-faq#reviewactivations
Thanks
Basj,
Stardock Community Assistant.