Unfortunately, the camera has no lens cover LX7. Only an antediluvian lid, which you must remove again and does not know where to put it. The LX7 has a filter thread with which you can attach filters to the lens. This cover allows the screwing of a filter under the lid.
The part is stuck, if you have screwed it right. For this purpose it is necessary to remove the lens has a front ring and then unscrew the part in the same direction of rotation accordingly. These are a type of bayonet lock without screw.