"Change Primary User" On Device in Intune is Greyed Out

I am an IT Administrator and have all the permissions to manage my businesses Microsoft 365 accounts including Intune. When trying to update and change to primary users for devices in Intune, it is greyed out and doesn't allow me to change it. I need to get this resolved so we can properly have all devices showing the correct users. How can I get this resolved? I've uploaded a screenshot to this message.