Offline computers & contacts in a separate group

Hi.  I suspect that a recent update to the Team Viewer system at the Team Viewer base location has created a problem with the displaying of the online and offline contacts.  We are licensed to use Version 12 of Team Viewer and have been doing this for a long time now.  The current release is up to Version 13.  We put a check mark in the "Offline computers & contacts in a separate group" box in the options, and it has always worked fine up until a week or so ago.  Now some of the "offline" contacts (but not all of them) show up in the "online" group, except that they include "(unknown)" on the end of their ID name.  So our "online" group contains our regular "online" contacts, as well as a bunch of "offline" contacts that include the "(unknown)" term on the end of their ID name.  I have tried un-checking the "Offline computers & contacts..." box, and then re-checking it, but the problem persists.  This happens on all of our Team Viewer computers, all of which are running release 12.  Can this problem be fixed?

Craig Peterson