My.openhab connected but not items/devices available

I installed the myopenhab addon. The log say the connection to myopenhab service was established successfully (“Connected to my.openHAB service (UUID=…”). I can access my sitemap via the web interface.

But in the webinterface of my.openhab the items tab shows now devices and devices tab says “No DevicesYou currently have no devices registered with my.openHAB”.

I also connected ifttt to my.openhab successfully but when I try to create a recipe, I have no items to select.

Any ideas?

You have to set up persistence.