There's a downlight in my bathroom that doesn't seem to have a secure connection. (Excuse the layman terms) The plastic cube at the end of the wire of the transformer has two holes which if you push the pins of the bulb to the metal connectors within the holes, it lights up, but you have to rest the pins within the holes using gravity to maintain illumination. Is it missing a part to hold tight the connection? I'm only aware of two types of pins - I refer to them as thin and fat (with the knob at the end). I'm using thin since the fat ones won't fit (yet the thin ones are too thin for the holes and therefore easily slip out when pushing up the bulb in the ceiling).