Does that mean that you have your item created in PaperUI and in addition in your default.items file at the same time?
Especially if they have the same names (Bad_Bewegung) in PaperUI and items file that “could” be a problem.
Does PaperUI show two items being linked to the channel Motion Alarm?
If not (and you still have your item defined in PaperUI and default.items), make sure that you define your item only at one place
If yes, try to delete the item that PaperUI created and only use or default.items (or the other way round).
Once you cleared your items, make sure to delete the cache of OpenHab:
There is a nice description here: Clear the Cache