I cannot imagine a set of 9mm Luger dies not having a full-length sizing die. It squeezes the fired case to below chamber diameter. If it is a carbide die, which it probably is, set the die so that it is just barely above (the thickness of a piece of paper or a bit less) the shell holder when the ram is fully raised. A little lube, a very little, can make sizing easier. The expander die brings the inside diameter of the case back up to the proper dimension to hold the bullet tightly and can be used to bell the mouth of the case to help when seating the bullet. A very small bell is all that is needed. Enough is enough. More is not better. The taper crimping die will be used to remove the bell so the round can chamber. The bullet will be held in the case by the case tension and not by a crimp. Do not be tempted to try to apply a heavy crimp. Try the finished round in a case gauge or, even better, the chamber of the barrel of the gun you will be using.
If it does not plunk in the barrel or gauge, there are several things that can be adjusted. .
Check to see if the sized but not belled cases fit into the chamber or gauge. If they do not, readjust the sizing die or try a different sizing die.
The overall length may be too long. The bullet may be engaging the rifling before the round is fully chambered. I have some 45 bullets that are a little fatter than others and need to be seated more deeply in order for the round to seat. Different bullets have different profiles and may need different seating depths. Seat to the depth that works and not to the depth given in some reloading manual.
The taper crimp may not be removing all the bell. Adjust the die to give a very small amount of additional crimp.
Seating or crimping may have bulged the case a bit if you had to use much force to do either activity. Neither should require much force.
Your components, especially the cases, may not be quite right. Not all headstamps and bullets are the same. Try different cases and bullets.
Some people use a Lee Factory Crimp Die to cover up any problems by postsizing the assembled round. I have several for different chamberings but suggest that the problems be fixed so the postsizing feature will not be needed. They do give good crimps even if the postsizing feature does not come into play. It is generally wise to seat and crimp in two different steps, and the FCD is not a bad choice for a dedicated crimp die.