Without a pic (and even then- may be hard to say why) its impossible to say. However- your best bet is to get in there and use your hands and fingers to trigger the reset and drop them and do this a number of times and basically just watch stuff move and feel how much force it is requiring. You could have a gummed up mech that’s simply not fully traveling- it could be a bent piece- it could be mid adjusted for height. All I can really tell you is that for just 4 targets the reset should be pretty easy and smooth. If your feeling much resistance at all it probably should be cleaned and then adjusted after you reassemble.