netwok not working any more

When I start YaST network settings, nothing happens (YaST freezes). ifconfig only shows the loopback interface. Before last update anything worked fine. How can I fix networking?

What ‘Other Version’ are you running? What repositories are active, perhaps pulled in an incompatible update?

cat /etc/os-release

zypper lr -d

openSUSE Leap 15.0. I did not have the time to upgrade. I made a rollback to an earlier snapshot with snapper and it works again.