The crimps datasheet should describe the diameter of accepted insulation and the length of uninsulated wire should be exposed for a proper crimp.
The pokey triangle section crimps onto the insulation to hold it in place. The u shaped section where your wire is, is the part that crimps for mechanical and electrical connection to the wire and crimp.
The section you are trying to shove the wire into, is not supposed to have wire in it. You stripped the wire too long for the crimp, likely by a mm or so. That section will make a mechanical connection to a mating pin.
Your problem is almost this. Your insulation doesn't extend into the wire crimp but the wire does extend into the terminal.
Here is a guide by Molex for proper crimping. https://www.molex.com/tnotes/crimp.html