all inventory slots full, gun in hands.Used hot bar to drink,character dropped gun on floor. Cannot pick up gun but can see in left column when inventory is open. Can unload ammo from gun and drag icon onto hot bar. Character acts as if he has invisible gun in hands i.e. aims when pressing right mouse button. Logged out to try and fix, logged back in, character has gun in hands plus there is a gun on the floor which I can now also pick up.