General issue


I upgraded from 2.5.11 to openhab 3 via openhabian on da Pi 3 B.
The only binding running on this System was the shelly binding. All Items where createt in text and the link also happend in the items file. I didn´t hav a things file.
Now it seems, the items are there, but I can´t control anything- due to the missing link between item and thing? Do I have to add all the things again in order that oh3 works as 2.5 did?
Should I start from scratch with the semantic modeling?