Travelify theme wordpress site does not show featured image after version 3.0.9 update

After updating to Travelify version 3.0.9 my wordpress Web Site does not display Featurted images on my Posts anymore. what can I do

I still did not get any response regarding my listed problem raised 5 days ago, regarding “After updating to Travelify version 3.0.9 my wordpress Web Site does not display Featurted images on my Posts anymore. what can I do”.
I do find the same problem on three different Wordpress/Travelify sites, which I all did update the same day. When I switch to the Wordpress twenty-Twentyfive Theme all works fineand when I load an old Backup on Travelify 3.0.8 it’s also all fine.
Any recommendations?