Sitkadeer above has a good suggestion on the sharp "V" shaped spring that must sit beside, not under, the disconnector to put tension on it. Be careful putting the grip back on as the position of this spring is critical to reset. Also, the sear spring must engage the center of the sear in the "V" shaped bottom of the sear to properly reset on the long arm of the sear spring and the short arm of the sear spring must be centered in the back part of the frame itself. The sear spring may need the tension adjusted if it is not purring enough tension on the sear itself. Also, you did not say if the trigger has a set screw for overtravel. If so, it may be adjusted out too much not allowing the trigger to reset. Hope this info is helpful.
