Lite2 is NOT topre (hence the "lite"), all lite models are standard domes. You should try and return it, since unlike a true mechanical it's not as easy to replace an individual switch. Something is either wrong with the membrane or the dome, but the domes come in sheets so a single replacement will be sort of difficult. You can try and clean the conductive bit on the bottom of the dome and see if that helps, but it sounds like it's not making contact unless you push really hard.