New Luger. Can someone help tell me what I found?

[ithacaartist]

Sometimes this pin is not visible with an angled pic, whereas the pin is there, its end submerged beyond flush with the toggle's surface. With the action held open, you'd be able to spot the tail of the pin if it's there--sticking down enough to retain the axle pin-- through the hole in the center of the left knob. Looking down into the top hole, it should also be visible if extant. The latter way is the fastest, but the presence of a pin alone doesn't necessarily confirm that it's doing its job down below. Without the retaining pin, one can push the axle our easily. If the axle is mobile along its axis, the pin is indeed broken or completely missing.